Here's a great betting trick with a surprise finish!
The performer bets $50 that he can find a selection from a deck mixed by a spectator. He even places a fifty-dollar bill into an envelope, telling the spectator that the money is theirs if the performer can't find their card. It appears that the spectator has won the bet after a few wrong tries by the performer. When the spectator is asked to remove their earned fifty-dollar bill, the selected card is found inside the envelope instead! A magical surprise, and the performer wins the bet after all!
