Now, you can build your own open source multi-touch display. I guess it was at Maker Faire but somehow I missed it…
Researchers at Eyebeam, an engineering and design firm, sell kits that let people build their own multitouch tables. In this picture, the Cubit frame is completely disassembled. To make the display functional, users must add an inexpensive video camera and a projector, among other pieces of hardware.

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