Can’t afford a JazzMutant Lemur? Check out this video on making a MacGyver-style multitouch pad.
Building a small portable multitouch pad will allow you to test software and experiment on a smaller scale while building your full table or when away from your multitouch screen. This uses Front Diffused Illumination, with normal ambient light (infrared not required or needed) and a normal off-the-shelf webcam (IR filter can still be in place).
via audiotouch