This happened to me. I was in high school taking Calculus II at a state university. Since I arrived at the commuter campus of 17,000 later in the day (since I still was in high school) I usually rode my Yamaha 400. The approved M/C parking was the lined off triangles at the end of the aisles. That gave me up close parking, even at 1 in the afternoon. So, we are sitting there find the area under the curve, again, and a girl walks in and gives a note to the professor, who in turn gave it to me. The note said "Motorcycle driven over, come to parking lot".
I pack up my stuff and go out. There are the cops, my bike standing upright, and a car in the grass. Here's what happened, another student was backing out of his slot, realized he had no brakes, and just started rolling backwards. Backed over a handicapped sign, puncturing the gas tank in the process, and just barely nicked my rear turn signal, sending the bike on its side, and the car continued rolling into the grass, where the rest of his gasoline emptied.
The kid said he didn't want to involve his insurance, so just get a quote and he would pay it. I stopped a the shop on the way home, broken turn signal, scratched trunk, damaged grip. Dealer quote, about $500. Got home and called the guy and he found out that his car was much more damaged than he though, and just to turn it into insurance. Got a check a few days later. Turn signal off a wrecked bike, $28 and a new set of hand grips $8, and $460 in bar money to wash away the sorrows about the scratch.
On an unrelated note, I don't think grass ever grew in that spot again.