This is a lovely self-working small packet trick Aldo Colombini created from a trick published by Richard Vollmer.
You show the spectator two face-up packs with four cards each, and a prediction - in the form of a face-down card - is placed on the table. The cards are the same in each pile, but their order is different. From a regular deck of cards, the spectator selects three cards. The values of these cards determine how many cards have to be moved from the top to the bottom in either of the piles. The spectator is even allowed to split the work between the piles. Say 5 cards need to be moved. The spectator could move all five cards in one pile, or move one card in one pile and four in the other pile, or move two cards in one pile and three in the other, etc.
After each of these three randomization events, the top card of each pile is put aside as a pair. In the end, it turns out the spectator has only created one pair with matching cards. However, when the prediction is turned face-up it has predicted the matching pair. But that is not all. The climax is still coming. When all pairs are turned face-down so that the backs are revealed, it is seen that all four pairs have matching backs. Congratulate the spectator for his uncanny ability.
1st edition 1991; PDF 3 pages
word count: 1107 which is equivalent to 4 standard pages of text