Smithsonian Magazine:

THE EFFECT I cut a deck of cards a couple of times, and you glimpse flashes of several different cards. I turn the cards facedown and invite you to choose one, memorize it and return it. Now I ask you to name your card. You say (for example), “The queen of hearts.” I take the deck in my mouth, bite down and groan and wiggle to suggest that your card is going down my throat, through my intestines, into my bloodstream and finally into my right foot. I lift that foot and invite you to pull off my shoe and look inside. You find the queen of hearts. You’re amazed. If you happen to pick up the deck later, you’ll find it’s missing the queen of hearts.

Teller (the smaller, quieter half of Penn & Teller) gives the best explanation of a magic trick I’ve seen.