7) Richard Marcus – Cheating casinos with “past posting” technique

Richard Marcus, a blackjack and baccarat dealer by trade in Las Vegas, mastered the art of card dealing and discovered a way to cheat the casinos. He got renowned for his technique of “past posting,” where he’d wager low amounts and then secretly swapped out low-denomination chips for higher ones, garnering him huge sums of money.

Although he was apprehended by the authorities, he was never convicted and walked away with more than $5 million from casinos.