I can top all of those...
My mate was driving his car (that I had just sold to him), he had no Tax, no MOT, no insurance and only a provisional licence. He promptly gets pulled by the cops, and they get him in the car, have a massive go at him, take his car keys and tell him its getting impounded and he's going to court.
So he comes to me the next day panicking and tells me what happened, so to save any hefty impound fees, I tell him lets go to the station and sort it out. We drop by the police station and tell the desk cop what happened and to ask where the car was, but there was no record of my mate getting pulled over, and we we're both too stupid to remember the registration plate.
We left the station to go back to his to get the V5, and round the corner, where he gets pulled over, the car is still parked and locked at the roadside. I still had a spare key for it, so my mate jumps in it and shoots home, puts it in the garage and gets his licence two weeks later.
He hasn't ever heard anything about the incident since. Some police force we have eh?