Just imagine what it would be like if we could generate free energy. No need to worry about pollution, or fuel, or effort, or anything. It’s no wonder so many people have tried their hands at building ...

Perpetual motion machines. Like the philosopher’s stone, they don’t and will never work. Unless you are in the internet, watching this neat collection of looping animated GIFs for all eternity.

A perpetual motion machine is (as the name implies) a machine that moves perpetually; it never stops. Ever. So if you created one today and set it going, it would keep on going until the Big Freeze.

Perpetual motion—it's fun to say that. For some people, perpetual motion machines hold the secret to everlasting free energy that will save the world. To them, it's a machine that is just beyond our ...