MIT Media lab project:
'SixthSense' is a wearable gestural interface that augments the physical world around us with digital information and lets us use natural hand gestures to interact with that information.
Dialing a number with dialpad projected on hand:
The device consists of a camera, a projector, and a mobile for communication. Simple hand gestures are recognized and online help is available any time. If you want to take a picture, simple, just make a gesture of taking a picture and its done..
Or: Youtube link
Pranav Mistry is IIT Bombay Alumni, M. Des. 2005 batch from IDC IIT Bombay.