Bits and pieces.

[Thingo]

TrackIR uses camera based motiontracking for it's headtracking.
Maybe they could use their system to detect a single led placed on a hat, such as freetrack does, for simple 2 degrees of freedom headtracking. A standard xbox camera should simplify things. I had freetrack working well enough with a red LED and a $20 camera.

And theres nothing wrong with me flapping my arms when i'm alone.