The Gravity Gun from Half-Life 2 has always been one of my favorite video game guns, both in terms of design as well as use. It was always amazing to me that it took almost eight years for accomplished prop builders to take a crack at it, given how iconic both the weapon and the game are to the broader gaming community.

In December 2012, I decided to start on a build of it myself.

For the uninitiated, the Gravity Gun is one of the primary weapons and tools that you use in the video game Half-Life 2. It allows you to pick up and throw various objects in the game. You only get to see it from the 3rd person in a few instances, thankfully one of which is when another character in the game is holding it.

You can see the size of the weapon here, and I used this image to help determine the scale used when building everything. Coming from a 3D design background, my primary prototype building methods utilize laser cutting and 3D printed parts. Props from video games make the first steps easy, since in most cases you can easily extract a game model into a workable format. However there are a few caveats to this:

For a robot the size of a shoebox, OpenROV has made quite a splash in the submersible community in the past year. Just after MakerFaire 2012, where we saw OpenROV for the first time, it and its creator Eric Stackpole showed up in the New York Times along with a bold proclamation about the open source project: "It could change the future of ocean exploration."

Photo credit: NASA

Those weren't Stackpole's words, but you can bet he believes them--his quest for a sub-$1000 exploration bot recently landed him on the cover of Make Magazine, and OpenROV was back at this year's Maker Faire. Last August, Stackpole and his partner David Lang raised over $100,000 on Kickstarter for the OpenROV. What's surprising, considering how successful OpenROV was in 2012, is just how far the ROV has advanced in the past year.

"Even when we were doing that expedition to the Hall City Cave that ended up in the Times, we didn't really have a robot that was fully functional," says Stackpole at Maker Faire 2013. "You know, this is a maker product. It was on its way, there were some things that could work. We could drive it around, but the video feed wasn't reliable. Now we're at a point where we have everything we had dreamed of. Live video streaming, we can do high definition, it's going up to a computer. It's functional. This is the part where it really gets exciting. This is where we're going to start exploring, really exploring, places that haven't been seen before."

Photo credit: Make

Stackpole is a fountain of enthusiasm, but he's earnest when he says things like "this is the part where it really gets exciting," he means it. His obsession with ocean exploration came while he worked at NASA as a mechanical engineer, and last year he reduced his hours to devote more time to OpenROV.

Just in the past few months, the OpenROV project has made a major breakthrough.

In 2012, Roy the Robot was one of the most eye-catching projects on exhibit in Maker Faire's expo hall. Half of Roy's draw came from his Terminator-like skeleton, with laser-cut wood standing in for shiny metal. He owed the rest of his appeal to a red Hawaiian shirt that Hunter S. Thompson and Bruce Campbell would've fought over. This year, the Hawaiian shirt hangs in the corner of Roy's booth, because he's no longer wearing it--he's got a brand new laser-cut chest to show off. 11 months after concluding a successful Kickstarter, maker Brian Roe is drawing a constant crowd to show off the new and improved Roy.

"At Maker Faire last year I had the arm and the hand and just the head, basically, the eyes and the jaw," says Roe, who's a mechanical engineer by day. "It was all mounted on a PVC frame kind of representing the shape of a human body, but nothing underneath the shirt. That's why he had a Hawaiian shirt on. I wanted to cover up all the PVC. This year I decided I really wanted to try to finish out the arms. So I got working on the arms, but then of course, if you're going to build the arms, they have to attach to something. So then you need the chest. Well, if I'm going to put the chest in there, I might as well do a cool neck because I've got the chest there to hook the neck to. So it got a little crazy. Now he sits with 48 servos, 16 servos in each arm. It's crazy. There's a ton of servos."

Roe started Roy as an animatronics project before Maker Faire 2012. The scale of the robot quickly spun out of control, but in a good way--Roe kept adding degrees of articulation, laser cutting parts in his home workshop, and suddenly his robot had a hand with individually servo-driven fingers. Roe launched a Kickstarter the first day of Maker Faire in 2012, offering Roy arm kits for backers to assemble, and eventually raised about $15,000--double his goal of $8,000.

There was enough money and interest in the project for Roy the Robot to grow even more complicated. But first, Roe had to deal with laser cutting some 10,000 parts for his backers.

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.

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:

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.

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.