Mine was in a driving school car!
Came up to a very narrow T-junction in an old part of town with cobbled streets. There was a car parked directly opposite the road I was on. My instructor had given me instructions to turn right at this T-junction and I remember thinking that if I wasn't careful I would hit the parked car.
I got to the junction, braked, looked both ways, then my foot slipped off the brake onto the accelerator
My instructor immediately hit the brake on the dual controls. As it had been raining for the first time in 6 weeks, the roads were very greasy and I slid gently into the parked car. I still maintain that if my instructor had kept his feet off his controls I'd have got away with it.
Anyway, the story didn't end there. My instructor went looking for the owner of the car I'd hit. No-one in the street knew who it belonged to, so he was left with no option but to report it to the police.
I was out with a friend one night when there was a knock on mother's front door (about 10.30 pm). She opened it to find a policeman standing there saying it was about my accident. She panicked, thinking I'd been involved in something serious. But no, he just wanted to speak to me about crashing into a parked car and would I please call at the local police station for a word.
I went and had said word (or several). The first thing the police did was give me a notice of intended prosecution for driving without due care and attention. The second thing they did was thank me for finding the car which had been stolen and used on false number plates for some time.