Dan, even though you had to eat the $400 caused by that biatch I would have definitely done something to get even.
One time I was sitting in my car (87GT) in the school parking lot doing some reading. When this guy and his apparent g/f, or as I like to refer to her; worthless gutterwhore, pulled into the spot next to me in a ~98 Celica (riced out of course). She proceeded to forcefully "fling" her car door open and into my door. My car shook from the impact which to me would cause even the most oblivious person to look up. My windows were down and I had music playing so it was ridiculously obvious that I was there. Neither she nor her boyfriend made any attempt to apologize, and in fact didn't even bother to look over at me or that car. So naturally I was highly irritated.
I waited for them to leave then I got out to examine my car to which there was only slightly noticeable paint scratching. I then went over to the car and pressed as hard as I could and dragged the biggest key I had from just behind his headlight to about halfway though the passenger door. It made the most atrocious sound I had ever heard and went straight down to the metal
At this point I was satisfyed with my revenge and moved my car to a distant parking space.
People who have no respect for their own property, let alone yours, are all too common. I know it was actually the g/f that commited the act but I consider the b/f to be an accessory because of his lack of remorse and concern.