I feel your pain.. My car was keyed very deeply all along the passenger's side while I was parked at school. I took it to the dealer and they said the whole side of the car will have to be re-painted!
I got a new dent on Friday... I was at my friend's house and they're building a new garage... Only the foundation is done. It is maybe 6-8" above the ground.. Surprisingly, my PDC sensors didn't pick it up, and I couldn't see it at all. I didn't notice I hit it until I realized my car was no longer moving backwards... It left a good-sized gash in the bumper and cracked the paint on the corner of the bumper.

uch: