The expo hall of Maker Faire is packed with hundreds of projects. Some Makers are there to sell things they've built. Others are just there to show off something fun. Craig Bonsignore, maker of the Open Clock, had a slightly different motivation for his project: He hated his alarm clock, so he built one of his own as a completely open source project. And every component, from the 6.4-inch resistive touchscreen to the 512 LED red/green display, is available online.

"It's the maker thing. Something bugs you, you just make a better one," says Bonsignore. "The design criteria were: Easy to use, easy to see, intuitive. I don't sleep with my glasses on, so with my glasses off, arm's length, I can read the digits without squinting."

The Open Clock looks a little like the time-telling equivalent of one of those cheap calculators with oversized buttons, and its numbers are big enough to read from across a room. But it's hardly a simple project. In his quest to make the perfect alarm clock--or, at least, an alarm clock that he won't hate--Bonsignore has given the Open Clock a fun array of features.

The display is touch-controlled, so a simple tap will switch from displaying the time to displaying the date. Another tap can open up the menu and adjust the time, and tapping at the top or bottom of a digit increases or decreases the number (if you've ever had one of those alarm clocks that makes you press a button 24 times to cycle through every AM/PM hour, you probably love this idea already).

The clock is green during the day from 7 o'clock in the morning to 7 o'clock at night, when it turns red.

"The clock is green during the day from 7 o'clock in the morning to 7 o'clock at night, when it turns red. So it's intuitive that right now it's day time, it's 1:52, it's green," says Bonsignore. He gestures to the three different models of the Open Clock he has on display at Maker Faire. A rough plastic frame houses the earliest model. "This is the first one--it's been sitting on my nightstand for about a year. I've sort of refined it over time. I think I started it with green at night, but decided, hey--red, submarines, there's kind of a night vision thing--red is better. You actually have more receptors on your retina for green. Green is an exciting color, and red is a subdued color, so that kind of made sense...The brightness adjusts automatically so it doesn't bug you at night. I had to go through some iteration on that."

The second Open Clock model has a smoother black shell. The third is made from transparent plastic, which shows off the Arduino board and speaker inside the clock. The LED face on the transparent model is also noticeably brighter than the other two, which he explains:

We’ve now burned through a few gallons of very expensive silicone rubber to make molds of every one of the Halo Reach Needler prop's 12 individual parts. There are a bunch of Needler-shaped cavities that need to be filled with something, and in a similar theme to making the molds themselves, there’s a variety of ways to go about doing so.

Techniques and materials will vary depending on the final use of the piece, but for the purposes of this tutorial we’ll be concentrating on urethane casting resin and leaving out other plastics such as epoxy or polyester. I’ll cover solid casts, hollow parts, and translucent/clear pieces as well.

The most basic parts to be made will be the solid pour castings. For these parts I’ll be using Smooth-On’s product “Smooth Cast 320” and the detail bit that sits underneath the upper casing will be used as an example (apologies for the process photo, I didn’t have a shot of the completed master before molding.)

The initial step after removing your master part from the mold will be to apply a powder layer to all facing edges of the mold. Personally I use baby powder, but I have heard other propmakers use talcum as well. This may seem like an odd step, but this will help reduce bubbles in the finished part. You can think of the thin layer of powder like a paper towel over a spilled drink. Just like a napkin will wick up moisture, a thin coat of powder in your mold will allow the resin to flow more easily into detail edges. What you’re working against here is the surface tension of the liquid, which will have a more difficult time seeping into detail areas without this step.

I’m working on an Alien costume. I’ve got the suit. It was built for me, and it’s gorgeous. But I’m making the head myself, and it’s kicking my butt. The problem: I have too much time.

I’ve learned over decades of building that a deadline is a potent tool for problem-solving. This is counterintuitive, because complaining about deadlines is a near-universal pastime. When I worked with the amazing sculptor Ira Keeler on the space shuttle for Clint Eastwood’s Space Cowboys, Keeler was always proclaiming, “With a couple more weeks, this could be a nice model.” We’re conditioned to believe that the deadline is working against us. But I’m not so sure.

I’d like the head I’m building to be animatronic. The lips would curl back and the jaws would open and snap out, just like in the movie. I’d also like all of these to be controlled by the wearer’s facial movements. I know how each of these actions should work individually, but I keep getting stumped when it comes to choreographing them all to operate together. And when I’m stumped without a deadline, I tend to let things go. So the head has pretty much sat on my bench for seven months.

Any cursory perusal of a fan/maker forum on the web reveals two distinct kinds of projects: the long, meandering, inconsistently updated but impressively detailed effort and the hell-bent-for-leather, tearing-toward-a-deadline build. Solutions to problems of the first type are often methodical and obvious. Solutions for the second type are much more likely to be innovative, elegant, and shockingly simple.

Invariably, the second type of project is propelled by an upcoming event: Comic-Con, Halloween, or even just a visit to a children’s hospital with the 501st Legion (a loosely knit group of Star Warscostumers). Deadlines refine the mind. They remove variables like exotic materials and processes that take too long. The closer the deadline, the more likely you’ll start thinking waaay outside the box.

Meanwhile, my alien head sits there, taunting me, awaiting its resurrection.

Have you ever thought about how odd it is that stacks of money, or diamonds, or dollar signs, or gold bars, aren't the icons we associate with slot machines? These machines are designed to do one thing, and one thing only: keep us playing. To catch us in a loop, to make us want to win, to make us keep playing and playing hoping to see those symbols line up and spill out a jackpot. We know slot machines are about money, but the iconography we associate with these machines is not dollar signs or gold coins. It's fruit.

99% Invisible recently devoted a 20 minute episode to the ingenious (and insidious) design of slot machines and how they've evolved. And those fruit icons have a long, long history.

Photo credit: Flickr user andresrueda via Creative Commons.

"To circumvent anti-gambling laws in the US, early slot machines masqueraded as vending machines," says 99% Invisible. "They gave out chewing gum as prizes, and those prizes could be redeemed for cash. That’s where the fruit logos come from. In fact, in the UK, slot machines are called 'fruit machines.' Despite outward appearances, slot machines have evolved dramatically since they first appeared in 1895."

That evolution is fascinating, since modern slot machines actually look fairly similar to models from half a century ago. They now have bright LCD screens and buttons to more rapidly start new games, but the visual language of slot machines is more or less unchanged. They still use fruit as icons. They still have levers on the side, which are totally optional--in a computerized system, the lever is simply a novelty. They're now called "legacy levers."

If you've ever wondered what the classic "BAR" symbol represents, it has a similar story. "The near-universal BAR symbol, which I always thought represented stacks of bars of gold, is actually based on the logo of the Bell Fruit Gum Company," says 99% Invisible's Roman Mars.

The three-reel slot machine design has been around for more than 100 years, and it's still what we think of first when we imagine slot machines. But many of today's machines are far more complex, even though they retain the same visual sensibilities. They'll feature multiple rows and columns of matchable objects (including fruit, of course) that produce hundreds--if not thousands--of possible combinations.

As any attendee of Bay Area's Maker Faire can attest, jaw-dropping projects can be found in almost every nook and cranny of the San Mateo Fairgrounds where "burning man for nerds" has mades its home for the past eight years. That was absolutely true this year: tucked away in the corner of the darkened Fiesta Hall (where the Tesla coils and EL-wire projects typically live), and far away from the main Expo pavilion, was the booth of small startup Technical Illusions. You may not have heard about this company before, but its founders' former employer was Valve Software, and its team is composed of ex-engineers from Valve's disbanded hardware initiative. Jeri Ellsworth and Rick Johnson--with the blessing of Valve--were able to take the project they were working on and continue developing it as a commercial product. That project, augmented reality glasses called castAR, made its public debut this past weekend at Maker Faire, and we were able to test them out in early demos.

We spoke to both Jeri and Rick on camera about the development and their hopes for castAR, and will have that video on the site this week. But here's a quick explanation of how it works, what the experience is like, and why it's nothing at all like the Oculus Rift.

castAR is a pair of active shutter glasses, much like the stereoscopic 3D glasses that were popular before the passive polarized glasses used for most 3D TVs today. Each lens flickers at 120Hz, but instead of showing a 3D image that's displayed on a static TV or monitor, they're made to view images projected from the very glasses themselves, bouncing back toward the lenses from a special reflective surface. Two tiny pico-projectors sit on top of each lens to display left and right images, which are aligned so that you're always seeing a 3D image as long as you're looking at the reflective table surface--there's no framing around the image as there would be around a TV. That means no matter how you move your head around, you'll always see the "screen" since the projectors are moving along with your head.

But the special sauce that makes castAR work is head tracking.

Last year, Formlabs raised almost $3 million on Kickstarter for its Form 1 3D printer, which we got a chance to see at World Maker Faire in New York. Unlike most desktop 3D printers, which melt and extrude plastic to form objects, the Form 1 uses stereolithography--basically, it cures a liquid resin with a laser, which can make for much higher resolution prints than extruded plastic. Now the Form 1 is finally shipping to its Kickstarter backers, and hardware expert Bunnie Huang already has his hands on one. Naturally, he immediately took it apart to see how it works.

Huang has written some cool teardowns on his blog in the past, like this look at how Chinese vendors can turn a profit on a $12 unlocked phone. When he took apart the Form 1, he noted how easy it was to disassemble with nothing but a 2.5mm hex key. That was the only tool he needed to take off the Form 1's orange plastic shield, which protects the eyes from the printer's blue laser and protects the printer's resin bath from ambient light, and to take apart the printer's base and frame.

Photo credit: Bunnie Huang

Once Huang had the Form 1 opened up, he walked through its various components. Here are some interesting tidbits about the Form 1's motors:

FIlm buffs thinking back on the history of digital effects will probably bring up 80s classics like Tron or Star Trek II: The Wrath of Khan, which featured cinema's first entirely computer-generated sequence, courtesy of ILM. But if you want to get picky, the use of digital effects in film goes back further than that. All the way to 1973, in fact. Today's CG space battles and green screens galore owe it all to Westworld, written and directed by Jurassic Park writer Michael Crichton.

The New Yorker has a fun profile on Westworld's effects, which were, of course, archaic by today's standards. The film was shot on a skimpy $1.25 million budget--small money, even at the time--and only a couple minutes of the film required digital effects. Westworld is set in a sci-fi resort, where visitors can spend $1000 a day to hang out in Medieval World, Roman World, and Westworld, which recreate classic time periods with robots serving as stand-ins for real people. Before the Star Trek holodeck came around, this was sci-fi's best take on recreating a paradise version of the past.

Things go wrong, of course--the robots go haywire, and cowboy Yul Brenner hunts star James Brolin across the resort. He is, in every respect, the proto-Terminator--including his "computer" vision, which is muddy and pixelated. Enter the first digital effect.

Lucas' Industrial Light & Magic wasn't around to whip up snazzy digital effects yet, so "Crichton got a quote for generating the computer imagery from the Jet Propulsion Laboratory in Pasadena," writes The New Yorker. "He was told that the two minutes of footage would cost two hundred thousand dollars and require nine months—both prohibitive. He turned to a maker of abstract films, John Whitney, Sr., famed in art and film circles for his work creating animation with military-surplus analog electronics and motor assemblies. Whitney referred Crichton to his son, John Whitney, Jr., who was eager to follow in his father’s footsteps as an experimental filmmaker, but using computers. He agreed to do the effects in four months for twenty thousand dollars."

Whitney's idea was to divide the film into squares and calculate the average color in each one, blurring them together into what we would now immediately call a pixelated look. But there was another problem: scanning the film back then was no easy task. Whitney found a company that could help him, and spent two months testing out how to play with color and contrast to make the effect work projected on a screen.

The New Yorker writes: "Because Whitney didn’t have a color scanner, the workload was tripled: M.G.M.’s optical department made color separations of the film—one set of black-and-white footage for each of the three primary colors—that he needed to process separately, image by image. The computer processing itself took about eight hours per ten-second sequence."

Found footage movies are in the zeitgeist again, even though many thought it was a one trick idea with The Blair Witch Project. But the enormous cost to profit margins of the Paranormal Activity movies launched the trend again, and it crossed over to other genres as well, like the comedy Project X, and the superhero movie Chronicle.

Whether it’s a horror story or a comedy, the idea is simple. An event happens, it’s been documented on video, and once the footage is found and watched, it tells the story of the event. The idea of a found footage movies seems so simple, you’d think anyone could do it. In fact, that’s been the appeal for many filmmakers: it’s a simpler, and much cheaper, way to make a movie.

Some feel that Blair Witch had a punk, DIY sensibility that proved to young directors they didn’t need a lot of fancy, schmantzy equipment to make a movie. As Josh Leonard, who starred in the film, told the L.A. Times, “It was like when you and your buddies were 14 and you heard a Germs album and you’re like, ‘I could do that.’”

Paramount has a number of found footage projects in development, and as the President of the studio, Adam Goodman, told Deadline, “I believe it’s something that’s here to say. It’s a terrific medium for filmmakers. They don’t see the medium as a barrier to entry. They don’t care about shaky cameras. For whatever reason, it just makes for a much more visceral experience for the audience.”

At least one horror director complained to me that doing a found footage movie makes directors lazy, but in several found footage horror films it took a lot of work to make it look like no work went into it at all. Since the late sixties, documentary techniques and cinema verite became a big part of making horror films effective.

Night of the Living Dead may have been the first in this regard with its frantic camerawork, and fake newsreel footage that helped make the event seem more plausible. And as Dan O’Bannon, the late screenwriter of Alien, said of horror films that were shot on a budget, the lack of professional polish makes them feel far more removed from Hollywood. Like demented home movies, you have the feeling the people behind the camera aren’t bound by any restraints and could show you anything.

Blair Witch was shot on Hi-8, which is essentially a step above VHS, and it definitely gave it that demented home movie feel, but it was actually a European horror flick shot on 16mm that first started the found footage concept, namely 1980’s Cannibal Holocaust.

BMX biking became a phenomenon in the 1970s as kids started imitating off-road motocross races with their own bicycles. By the middle of the decade, BMX racing was an organized sport, and bicycle companies were designing bikes specifically for BMX competitions. But the success of one of those brands can be traced back to one specific moment: the day Steven Spielberg's E.T. the Extraterrestrial premiered in theaters. That brand was Kuwahara.

Kuwahara, along with a group of local bikers from Torrance, California, gave E.T. its most iconic scene. After E.T.'s release in 1982, everyone wanted a Kuwahara bike. A man named Howie Cohen, who owned a bicycle shop in Torrance, supplied the Kuwahara bikes for the production after being told he'd be able to sell the exclusive licensed bikes of the movie. The choice paid off--E.T. became one of the highest-grossing movies of all time, and Cohen helped distribute Elliot's Kuwahara bike to a thousand distributors across the US.

The Kuwahara bikes were only half of the recipe for success, though--E.T.'s inspiring three-and-a-half minute chase scene wouldn't have worked without the eight stunt bikers who filled in for Elliot, his older brother Michael, and their friends. But as Narratively's story "The BMX Boys of E.T." reveals, the kids were never credited for their stunt work. Of the eight, only one has a credit on IMDB; none of them have their names in E.T.'s credits.

The story of how they made it into the movie is a lost bit of trivia about one of Hollywood's great movies. It starts with Spielberg telling his nephew and his nephew's friends what BMX brand he planned to use in the movie. They shot it down and said he should use Kuwahara, instead--the brand had a heavy presence in BMX magazines and was popular among BMX bikers at the time, but wasn't well-known outside those circles.

Photo credit: Howie Cohen

The next key moment came when Robert Cardoza, a BMX rider who worked at Cohen's shop, delivered the Kuwahara bicycles to the set. Spielberg told him what kind of stunts he had in mind for the film's chase scene, and Cardoza told him there was no way the actors could pull off the tricks. He showed Spielberg some of his own BMX tricks. That landed him the first stunt rider position in the film. And then he directed producer Kathleen Kennedy to a local BMX track, where she would find several more skilled riders to serve as doubles.

Narratively tells the rest of the story of the riders filming E.T.'s chase scene, how they saw the film early, and how they discovered they weren't credited in the film. Audio clips from interviews with Cardoza and Cohen also pepper the story. Each one is a must-listen if you're interested in the story behind the iconic chase scene.

Although the late William Castle, the man who gave us such films as Macabre, The House on Haunted Hill, and The Tingler, had a reputation for making schlocky, low budget horror movies, he was recently called the first interactive filmmaker. And indeed, his gimmicks did make audiences an active part of the movie going experience, even if an inflatable skeleton floating over the audience, or seat buzzers zapping you with mild electrical current wasn’t as innovative as creating IMAX, Dolby Atmos sound, or even D-Box.

Castle was somewhat of a low budget Hitchcock, and much like the master of suspense he would appear in the coming attractions of his films, explaining what kind of low budget fun the audience had in store if they went to his movies. Like Hitchcock, Castle become a brand of his own, and a recognizable face to young horror fans growing up. (Castle would even appear at the local movie theaters, talking to fans, chomping a big cigar, asking them what they thought of the picture.)

It all started with his 1958 horror film Macabre. Castle knew he couldn’t make a movie as scary as Hitchcock, but he hatched a fun plan to bring audiences to the theaters. As Castle recalled in his autobiography, he heard that Lloyds of London would insure anything, and he got them to put up a million dollar policy for anyone who died of fright watching the movie.

“Nobody’s going to drop dead,” Castle assured them. “It’s just a publicity stunt.” The movie began with a ticking clock, and an announcer warning the audience: “Ladies and Gentlemen, when the clock reaches sixty seconds, you will be insured by Lloyds of London for one thousand dollars against death by fright during Macabre. Lloyds of London sincerely hopes none of you will collect.”

Audiences ate it up, and Macabre was a big hit. With the House on Haunted Hill, which starred Vincent Price, Castle came up with “Emergo,” where an inflatable skeleton floated above the audience on a wire. Once time the skeleton fell into the audience, who tossed it around like a beach ball, and at another screening, the kids in the audience threw trash at the inflatable for target practice.

Then came The Tingler, which also starred Price.

Adam joined John Landis yesterday to discuss the legacy of Ray Harryhausen, who died yesterday at age 92. Harryhausen was a film effects pioneer, known for his work with stop-motion animation. You can see his work in films such as Jason and the Argonauts and Clash of the Titans (1971).

To hear the full interview, click Read More below.

I like to build PCs. Not as much as our resident PC columnist, maybe, but I still get a real kick out of ordering a bunch of components and spending an afternoon putting a PC together. I think that earns me a little nerd cred. But you know what earns you a LOT of nerd cred? Building a fully functioning PC—in Minecraft.

My favorite thing about projects like these are that not only are they an incredible example of the maker spirit, they’re a great teaching tool for something a lot of people don’t understand—how, at a deep level, the computer they use every day actually works. Today, we're going to look at some of the crazy things people build in Minecraft and other video games, and how they explain some of the most fundamental lessons of computer science.

The Basics of Turing Machines

If you spend very long hanging out in the sorts of seedy places people where gather to discuss building virtual computers, you’re going to hear the term “Turing Machine” thrown around. For instance, you might have seen that somebody built a Turing Machine in Dwarf Fortress but I’ll be damned if you’re going to be able to figure out what that thing does just from looking at the diagram.

So let’s talk a bit about Turing Machines. It’s a complicated topic, but also a tenant of modern computer science—so if you can pick this up, consider your daily enrichment quota fulfilled.

Photo credit: Flickr user maria_keays via Creative Commons.

A Turing Machine is a conceptual machine composed of four parts: