What a great topic S.Mc.C! Unfortunately I've never been bumped. Not once! ... Guess I'd better pick up my act.
Actually, I have bribed a train conductor so that we could have the entire carriage to ourselves. Does that count?
I have a friend who dresses nicely on all flights because she's convinced that it'll get her into 1st class. When I asked her wether it had ever happened she said "Oh... no, but it will. I can feel it."
But maybe asking politely would work just as well.