I've used ShapeTape -- it was at SIGGRAPH 2001. It was being hyped as an alternative to motion capture, i.e. you'd wrap the tape around important limbs of your actor and it'd sort of figure out where they were. It seemed to work "OK"; it _was_ cheap as hell though. Basically, the inside of these tapes has fibers arranged like so:

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Only it goes on much longer, and has more fibers. Based on the degree each fiber is bent, you can figure out the bend profile (it alters the way light reflects back).

Cool stuff. Not as flexible as true mocap though.

--Dan