Rabbits' Magic Pocket
It's a computer
Setup
For this trick, you need to prepare the deck in 4 chunks from ace through king. So on top of the deck when face-down, you should have an ace, and on the bottom a king. You don't need to arrange them by suit, to make it less suspicious.
Start by giving the deck some single cuts or false cuts. The spectator can do it too. Then, place down the deck on the table and close your eyes.
Ask the spectator to take out a small packet of cards from the deck (about 10 cards), and place them inside the box.
You can now open your eyes, and tell the spectator a deck of playing cards can be used as a computer. To "program" it, give it false cut. While saying "the deck has been programmed", take a quick look at the value of the bottom card.
Next, subtract the value of that card to 13, and deal off that many cards from the deck, while making it seem you're trying to feel a vibration from the cards. The card corresponding exactly have the same value as the number of cards in the packet the spectator took away.