Over in the motoring area, there's a question about what to do about scratches keyed into the side of a car. Reading that prompted me to remember this:

A mate owns (or rather owned) a new Porshe 911. One day, on returning to it after it had been parked in Brighton for several hours, he found that some SOB had scratched the words "F*** OFF" down the offside. Nice, deep scratches into the steel. Much swearing ensues.

On the way back home, he was sat at a set of traffic lights and a group of lads in a Golf GTi pulled up alongside. They started gesticulating and furiously revving the engine in the Golf. He wound down his window and indicated the side of the Porsche with a wave of his hand. They all looked down and went ballistic.

He still wonders if they thought he'd done it to the car himself, on the offchance of running into them.......