Back in the seventeenth century, scientist Robert Boyle devised a perpetual motion machine that he claimed would enable a flask to refill itself ad infinitum. It didn't work. But in this video by Munchausen Today (who "publishes videos created on pseudo-scientific beliefs, unproven facts, false evidences, not-patented inventions and my own crazy ideas"), Boyle's thermodynamically impossible device is finally realized. With beer.
The concept was that capillary action, which creates the meniscus of liquid seen in containers and is responsible for the flow of water from a tree's roots upward against gravity, would allow the thin side of the flask to draw fluid up and refill the cup side. In reality, this is not possible because surface tension will hold it in a droplet at the end of the tube rather than letting it fall. In the video above, the hydrostatic equation is used to suggest that the device works with carbonated beverages (it doesn't; the video's apparatus has a hidden pump) because the weight of the liquid is much greater than that of the foam. Of course, the hydrostatic equation doesn't apply to a flowing liquid!
Incidentally, Boyle's Flask would work and run perpetually if it were loaded with a superfluid, which, under ideal conditions, has a viscosity of zero.
Read more at FYFD.