Autodesk researchers develop 'magic finger' that reads gestures from any surface (video)

DNP Autodesk magic finger

By combining a camera that detects surfaces with one that perceives motion, Canadian university researchers and Autodesk have made a sensor that reads finger gestures based on which part of your body you swipe. The first camera can detect pre-programmed materials like clothing, which would allow finger movements made across your pants or or shirt to activate commands that call specific people or compose an email, for instance. Autodesk sees this type of input as a possible compliment to smartphones or Google Glasses (which lack a useful input device), though it says the motion detection camera isn't accurate enough yet to replace a mouse. Anyway, if you wanted that kind of device for your digits, it already exists -- in spades.