George Blake's Perfected Five Card Trick is a KILLER! Blake teaches multiple variations of the Rusduk Enigma.
The effect is simple and deceiving: The spectator takes a deck of his own cards and chooses five (no force). The cards are revealed, and the spectator is asked to think of one card of the five and set it aside. The magician picks up his phone and calls a friend. The friend tells the spectator exactly what card he is thinking of!