The following video is a nice demonstration of a multi-touch table game, Oculusia. The game was created by four students from the Aalborg University, Copenhagen, for Medialogy 2008. The students, Jens Fursund, Thomas Frohlich, Thomas Miksa, and Tobias Brogaard, also created the table.
Students Explore Multi-touch with Oculusia
The "Workbench" used in the Medialogy Lab at Aalborg University, Copenhagen:
"The Workbench displays 3D stereo images and the tracking system allows for interaction with virtual objects on the display surface. The tracking system uses infrared light to illuminate the display surface and the camera is only sensitive to infrared light. Basic image processing techniques are then applied to acquire position of the hand."
A Multi-Touch DigitalPainting Application pdf (Søren Støvlbæk, Larsen Gavin, Francis Murray & Jesper Højgaard Pedersen:Institute of Electonic Systems, Computer Vision, and Graphics, Aalborg University 2007)
The ReacTable: A Tangible Musical Instrument pdf(Martin Kaltenbrunner, Music Technology Group, Universitat Pompeu Fabra, 2006)