Clutch cable - it broke on my way to work today. Not ten miles from work, I just pulled off the interstate and was luckily right across the road from a gas station, about to make the last stretch through the desolate countryside, when my clutch lever slammed into the handle and the bike lurched and died. The damn nubbly thing that catches in the slot of the lever ripped right off and dropped to the ground. Sad me had to wait through a terribly long day, hoping not only that my local bike shop would have the new cable, but also that the bike would still be there when I got back. So, here's the moral of my story. Be prepared for anything.
-Chris Gerber