Jim Crooks pointed me to an experimental group who have created bizarre things from cornstarch. Their techniques are simple: a basic solution in a drum, oscillated at a specific frequency and amplitude. Then they inject puffs of air, and simple holes are formed in the liquid. But at certain frrequencies and amplitudes, the holes will persist indefinitely. And at certain frequencies, the holes generate creepy, writhing structures that dance across the entire surface of the drum.

The linked site contains a movie (you should watch it all the way through to the end!) and a pdf detailing the specifics of their experimental apparatus and their findings.

This is almost straightforward enough that a home tinkerer could duplicate it in a basement. Oh, if only there were time...