EFFECT: The magician removes a playing card from his pocket and leaves it face down on the table as a prediction. A card is then selected from the pack (let's say the six of clubs), but when the magician's prediction is turned over, it is found to be the ace of spades! The magician suggests that the audience, "take acloser look at the prediction."
Upon closer inspection, printed in small letters on the face of the ace, the audience reads, "I know youchose the six of clubs." Just a reminder to always check the fine print!