This is a great card effect requiring no sleights. It was invented by Paul Curry and billed as the trick which once fooled Winston Churchill.

There are more modern version such as Galaxy, but this one hits just as hard. If you can false shuffle the entire deck, it's even better.

The effect is this: A spectator deals the cards face down into two piles, one pile of red, and one pile of black. The magician tries to influence her by power of thought into which piles to place the cards so they are the correct color. The spectator has a completely free choice, but whether she tries to cooperate or not with the magicians thought power, when the cards are turned face up they are all proved to be placed correctly. Since the chances of that happening are 1 in 2^52 (ie 2 multiplied by itself 52 times) the effect is truly "Out of this world".

Secret