But, this was fun when I was a teenager:
Get a bunch of helium balloons and paint faces on them with glow in the dark markers - hang them at different heights, turn on a fan and turn the lights off. Voila - a room full of dancing, glowing faces. Try not to laugh.
βWhat goes on inside is just too fast and huge and all interconnected for words to do more than barely sketch the outlines of at most one tiny little part of it at any given instant.β - David Foster Wallace