I have the Oregon Scientific ATC2K:

PROS:
Cheaper ( I think I paid $90)
Small
Mounts on Bike or Helmet
Takes standard SD Memory Cards and AA Batteries
With a 2 Gig memory you get about hour and 30 minutes recording time at the best resolution
captures sound also
Easy to edit on the PC with standard video software
In good lighting you can get decent quality

CONS:
Battery life isn't the greatest, so I got rechargeable ones
Poor performance in freezing weather (camera shuts off), they suggest Lithium batteries for the cold but I haven't felt like putting that kind of money into batteries
Quality is OK for the web and PC, but not something you would want to watch on a wide screen TV
In dim light gets a little grainy looking, camera does not self adjust for lighting conditions.