Quote Originally Posted by Rich-n-Texas
I'm a gun owner.

It's my gang buster.

I'm just kidding.
I parked in an underground garage years ago under my apartment building. The passenger in the Buick parked to the left of my Volkswagen used to toss open his (or her, never saw the person), and put a little dent in my VW's door almost every day.

I put some masking tape in the affected strip on the side of my car; this reduced damage and clearly showed what was happening -- to no avail.

One day, returning from the gun club, I took a used target with some very nice wadcutter holes, folded it and wrote on the back, "Please be award that your passenger often dents my car which parks next to yours. Please ask him to be very careful opening his door. Thanks very much". There was never, ever another dent after that.