The FingerPainter™ point-and-click system, method, and device is a mouse-replacement in which the “mouse” is just the human hand itself.  The “pointing” function is provided by rays reflected off the human hand onto a surface, and the “click” function is provided by speaking the word “click” or “right-click” or other term into speech-recognition software.

The FingerPainter patent application was filed in 1997 but abandoned as a result of not having enough resources to pursue both the FingerPainter and the various Orang-Otang products.

Update:  Google now appears to be building an embodiment of the FingerPainter approach.