Researchers over at Microsoft have developed TouchLight, a touch screen technology that combines off-the-shelf components to create a unique and interactive affair. Several different types of cameras are positioned behind a holographic projection material screen recording your movement. Approaching the screen, you then see a projection of yourself or whatever you have touching the screen. This opens up several different types of applications, not least of which is the normal touch screen activities.
This is really one of those stories where seeing is believing, so be sure check out the fruits of Redomnd's research and start thinking about ways to abuse it like we do with a Xerox machine.
Microsoft's TouchLight 3D Technology [SlashGear]