This is a great experiment to create a really cool effect. You simply take cornstarch add in some water until it forms a thick consistent mix. Add the mix to an old sub woofer. You want to make sure its old, because this is going to pretty much ruin the speaker. Place the Cornstarch mix in the speaker and play a 120hz wave through the speaker. You can find sound modulators online that will allow you to play specific frequencies through your speaker. Blow a little air into the cornstarch and a very interesting thing begins to happen. Little creatures form in the cornstarch and start to dance.
This is a really fun experiment. It could be used to make a pretty cool music video, if you cut out the sound and added another track. Try adding food coloring or the solution from a glow stick. Have fun.