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xkcd #2924: Pendulum Types
(imgs.xkcd.com)
Alt text:
The creepy fingers that grow from a vibrating cornstarch-water mix can be modeled as a chain of inverted vertical pendulums (DOI:10.1039/c4sm00265b) and are believed to be the fingers of Maxwell's Demon trying to push through into our universe.
My bad, I chose the first example video I could find that was less than five minutes long. I previewed it, but without audio since I was at work.