Effect:
A spectator removes a bunch of random cards and then lays them out face down in front of you. None are of the cards are known to either of you. You make a prediction and begin to secretly write something on a piece of paper, which you then fold and place into her pocket. She then freely eliminates all the cards except one...you could not have known what that final card would be, you didn't even know what those random cards were, yet she opens the folded piece of paper in her pocket and you have successfully predicted that very card. Works every time!