The HD Hero is a great way to capture action sequences. It is small, easily placed anywhere, and for its output it is pretty darn cheap ($300 including one of the mounts), heck it even takes decent 5MP stills.
At the core of this Pee camera system by Instructable user aejnarr, is of course a one dollar sample pee jar for waterproofing. camera wise, in it there is a small 808 pinhole key-chain camera. Those are really cheap cameras designed to be “spy” cameras. They hold no lens but deliver decent image quality.
Once the “camera” is secured with a piece of sponge, you can gaff it to a mast, a car a motorcycle or a helmet. (and from my experience, they also make a great web cam, just if you decide to have a calm chat after all that action)
Bonus: You can upgrade to HD for about $20.
[PeeCam 808 -the $12, 5 min DIY action cam! on Instructables]