Some I knew about, one I didn't.

I cracked ribs in an accident, which introduced me to a new definition of PAIN. (There's NOTHING you can do for them)

The one I didn't know about until some time later was my shin. I hit it REALLY hard on a piece of machinery at work, it was black and blue (Okay, normally you don't get a 6 inch long bruise from hitting your shin), sore for a long time, but thought it was nothing. A few years later, I was being seen by a doc in the Army for something completely different, and she asked my how I broke my leg. Huh, whadaya talking about, doc? She showed me on my shin and then Xrayed it, and sure enough, I had broken it and not even realized it. (High tolerance for pain CAN be a bad thing)