Top hatting is in fact an illegal technique of winning at roulette. This technique is a lot like past posting, only this time it involves the dealer.
This technique is sometimes used at land casinos when the dealer and player know each other and plan to cheat. The idea of the technique is that the dealer places a chip on the winning number after the ball lands. This action is very profitable because even if the dealer places only one chip, the payouts are 35 to 1 on one number.
No matter how easy and winning this technique may seem, it is very easy to reveal at land casinos. Due to surveillance cameras and pit bosses no dealer will be able to cheat and those that try end up in jail.