Finally, consider making a shock-absorbing "enclosure" by "potting" the device in a small block of silicone molding compound; you could wrap the Arduino in a layer of plastic cling wrap to seal it, then use a small mold to encase it in the silicone (routing the connectors and such that are needed for access exiting the mold). Once cured, you would have the Arduino encased in block of synthetic rubber; it could be easily mounted somewhere on the bike, and would likely survive much more than fall...
The only thing I would be worried about is connectors coming loose.
Thanks for the advice, right now I have a two axis accelerometer and a light sensor. I was planning on figuring out how to use them propperly as input devices and creating a system that reads speed and tilt data from my unicycle. But of course I then remembered my problem of falling down occasionally.
I'll find a reason
How much shock damage can an Arduino take?