SixthSense is the latest effort from Pattie Maes and Pranav Mistry. The setup features a camera, a projector, a little mirror, phone and colored caps. The components communicates with the cellphone that will access all the data you need. The system tracks the four fingers and recognizes various gestures (zoom in/out, take a picture, organize, resize). It's still a work in progress but its capabilities are just amazing.