Re:Table (Score 2, Informative)

You can even do it with a regular webcam and some IR lights - check out the forums at http://nuigroup.com/ I recently built my own touch table from scratch - some IR lights point at a perspex surface, and an old projector back projects onto the perspex to provide a picture to interact with. The webcam has a small IR filter attached to the front, and this cuts out the regular lights. When my fingers touch the surface, they create hotspots that are tracked (known as Diffuse Illumination). You can also put the lights along the side of the perspex, and create a surface that uses FTIR (frustrated total internal reflection). So there are two ways of achieving similar results to Surface. If you are interested, check out nuigroup - everyone is very helpful if you run into any problems