[Christopher Jette] did a amazing job converting a 56″ rear projection television into a multitouch display. His original inspiration came from this drafting table project. The screen is a large sheet of 1/2″ acrylic with a screen material attached to the back side. The screen edge is surrounded by 168 IR LEDs. When a finger tip touches the surface it scatters the LEDs’ IR light. A webcam sees this scattered light and determines where the fingers are. Inside the box is a standard video projector. This is a great reuse of old equipment and we love to see a hobbyist making up ground where manufacturers aren’t. For more info on multitouch projects, we suggest the Natural User Interface Group. Here’s a video of [Christopher]’s display in action: