I've done martial arts for years and it has come in handy a few times, the one time that sticks out in my mind was when I was riding past a row of parked cars and a guy swung his door open and I nailed it, fortunately I wasn't going very fast so I wasn't hurt, the guy decided it was my fault and came after me, ow he was fat, in terrible shape and didn't know a thing about fighting, blocked the few punches he threw punch to the solarplexus and a kick (with clipless cleat) to the face and he was done. called the cops andhe was still out cold whent hey got there but they searched him and he had a rather large foldong knife in his pocket which concerned me.

then there was the time a tourist wanted to fight me because he thought i looked at his girlfrined a a red light. another fat guy. I stepped onto the sidewalk and watched his get screamed at by the other motorists when he was still stopped and the light was green because he was busy yelling at me, eventually he drove off giving me the finger, not violent at all on my part but still funny.