Cachya

This program, instead of using emitting diodes or reflective material as head tracking points, uses a paper model of predefined shape in order to provide for head tracking with six degrees of freedom, and therefore a webcam is the only prerequisite necessary to achieve head tracking with Cachya. The author of this website didn't check personally how strenuous for the CPU this approach to head tracking may be, or how much reflection related problems it incorporates, but the programmers claim that good results can be achieved on their website. Those interested can download a trial version.