Here's a beauty of a multi-phase close-up card trick that entertains and astonishes!
In the first phase, a spectator selects a card (let's imagine a Queen), as well as a number from 1-4. After the magician places their card back into the deck, it is miraculously shown that the face-down deck now has four face-up Queens, each separated by the number of cards that the spectator named earlier!
In the second phase, the cards are placed into four separate piles, and one by one, the Queen (in this example) disappears from its pile - even with both sides of the cards shown! Finally, as a special kicker, one more pile of cards is shown - the Queens have magically transported from their previous piles all into this one pile.
If you're looking for an effect whereby your spectator's eyeballs pop out, you've just found it!