Homemade Multi-Touch Screen
Multi-touch screen using SparkFun's Breakboard Power Supply to power the infrared lasers. www.sparkfun.com/commerce/product_info.php?products_id=114
This Multi-touch screen also uses an ultra short throw projector, a frosted glass tabletop, vellum sheet on the bottom side, modified PS3 Eye webcam, Community Core Vision and Processing.
All of the software is Open Source and interfaces can be built using OpenFrameworks, Processing, Flash and others on Windows, OS X and Linux.