Any wall can become a touchscreen with this new Kinect hack.

The startup Ubi Interactive has developed a way to turn any surface into a 3D touchscreen. A projector assisted by a Kinect camera senses hovering and wall-touching hands. Their software works with windows, and 3D gestures such as waving or beckoning are in the technology’s future. Anup Chathoth, one of the developers, explains how the touchscreen works thus far:
It knows exactly how far your fingertip is from the surface—when you actually touch it, that’s a click; when you’re not touching, it becomes a hovering motion.
The software is still in its early stages, but opens up new interface possibilities. The throwing, grabbing, and gathering gestures of Iron Man and Minority Report may yet become a reality.