The Augmented Reality Sandbox 

The Augmented Reality Sandbox (orginally developed by researchers at UC Davis) lets users sculpt mountains, canyons and rivers, then fill them with water or even create erupting volcanoes. This version of the device at UCLA was built by Gary Glesener using off-the-shelf parts and good ol’ playground sand.

Any shape made in the sandbox is detected by an Xbox Kinect sensor and processed with open source software. It is then projected as a color-coded contour map onto the sand.