You can achieve much the same CPU-offloading effect with a $30 Wiimote, to be fair.
TIR is very good, it's just becoming easier and easier to duplicate its functionality for a fraction of the cost.
FaceAPI is another example of a piece of software that could do this very cheaply (not so cheaply for developers, however) using a $30 webcam. The only real caveat is that ideally the camera must capture at a high fps, not necessarily a high resolution, so a Playstation Eye or EyeToy camera is an ideal choice (320x240 @ 120 fps).