I was arrested for vandalising a sign when I was about 15. Cop puts me in the back of his cruiser. Car still running. He gets out of the front to confer with a colleague on the sidewalk who had just shown up. Once his colleague left, he returned to the cruiser I was sitting in, only to find that he had locked himself out. I was 15, so my arms were like tooth picks. I reached through a slight crack in the glass barrier separating the front and back seat and unlocked the car door for the cop. He looked around, looked down at me and said "have a good night, kid." and let me go. It was epic!