Today I made a bike-cam mounting bracket out of an M5 x 0.8 screw and nut, a random chunk of spare metal drilled, heated, bent, and ground, and a 1/4"-20 bolt and nut. The little screw goes where the front reflector threads on, and the bigger bolt fits the tripod mount for a camera. Here it is mounted below my left turn signal (click for a slightly bigger view):
The metal was left over from a failed attempt to build a tool to work on my VW Rabbit so it was nearly free.
I was a little worried that the spot-welded nut that the reflector threads into would snap off the first bump I went over due to the weight of the bracket and camera, but the 'Yamaha' sheet metal badge it's attached to has some give to it for shock and vibration absorption. It also means the video ends up being a little wiggly but not too bad (you can just barely see my fender at the bottom right of the below video as a reference point for the wiggle). If you want to watch it, you may want to skip ahead to 15 seconds in as the first bit is really boring:
I don't have a really cool video yet, unfortunately... this was just a proof of concept. :)
The project turned out ok, and really, half of my desire to make it was just to give me a reason to play with power tools, torches, and a sledgehammer... and it succeeded in that respect. The other half is, I thought it would be a cool thing to do after I watched a bunch of motorcycle videos on YouTube. One thing that you really notice on videos like that is that motorcycles are like airplanes when turning -- they really bank or lean. The interesting thing is that the lean seems much more radical on video than in real life. In the video, the corner was taken a fair bit faster than the recommended 10MPH (but still within the posted speed limit, I promise!), but it looks like I'm practically dragging a footpeg.