OK, I can't believe I didn't think of thise right off the bat:

This was maybe 2 years ago, when I used to bike to school. It was on a Friday, and I had a friend coming over to my house. Because he walked to school and didn't have his bike with him, I walked my bike to my house with him. On the way, we stopped by a convenience store, I propped my bike on a nearby tree, and we both went in and bought some stuff(he bought a lighter - don't ask!). It wasn't until Monday that I realised I never picked up my bike. Oops.

My family seems to have a lot of bad luck when it comes to injuries. My dad's dropped a boat motor on his foot, and had some woodworking accidents, so he's missing a toe, half a ring finger, and had to have the bone on his thumb filed down. My brother(who's only 19) has both badly burned and sliced up one of his fingers(on separate occasions). And, my uncle has broken almost every bone in his body, at least once, due to several skiing accidents.
Luckily, I've avoided any serious harm so far, but I'll keep you posted :P