1. When there's only one person in the elevator, tap them on the shoulder then pretend it wasn't you.
2. Ask if you can push the buttons for other people, but push the wrong ones.
3. Hold the doors open and say you're waiting for a friend. After a while, let the doors close and say "Hi Mike, how's your day been?"
4. Drop a pen and wait for someone to help pick it up, then say "that's mine!"
5. Stand in the corner reading a telephone book laughing.
6. Take pictures of everyone in the elevator.
7. When the doors close, announce to the others: "It's okay. Don't panic, they open up again."
8. Stand alone, and when the doors open tell people who try to get on that the car is full and that they should wait for the next.
9. Swat at flies that don't exist.
10. Ride naked.