Mind Control: In a crowded area, point and/or stare upward in a random direction with a surprised look on your face.
Time Travel: Imagine yourself in a familiar place, x years from now, waving. Commit this moment to memory. When the time comes, wave back.
Distort Reality: Keep a list of absurd and fantastical topics of conversation in your pocket or mind. In a public place, where others can’t help but hear you, either pretend to discuss these subjects on your phone or bring a friend.
Psychic Vision: While walking, close your eyes and see how far you can make it.