You didn't get caught up in that Back to the Future time circuit hoax last week, right? (For the record, the "future day" Marty visits in the film is October 21, 2015--still over three years away.) But the Photoshop hoax was timely in that it coincided with the debut of this awesome prop recreation from Adafruit Industries. Adafruit's Phil Torrone posted his worklog of this time circuit recreation that he made using parts sold by the company. Starting with nine of these brilliant 4-digit LED displays (that do come in red, green, and yellow), Torrone assembled and soldered the faux time circuit components--anchored by a Teensy microcontroller--on a protoboard but then laid them out "dead bug" style inside a laser-cut acrylic chassis. The label decals were just printed on an inkjet and cut out with an x-acto knife.
Torrone says Adafruit can't sell kits for this build due to copyrights, but lists all the components you need to build your own time circuit at the bottom of his post.