From the ThinkGeek.com Description
Simply fill the tank on the top of the Aqua Dance with water then push the pump a few times to pressurize. Turn the lever beneath to control the size and speed of the water beads as they drop repeatedly out of the tank. With the reduced friction the natural surface tension of the water takes over to create some unusual liquid dynamics. You'll find beautiful patterns in the water that are different each time. The ridges and funnels on the surface scatter the water in unpredictable ways as it zooms like quicksilver to the bottom.
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