The Drinking Bird

Description:  The drinking bird is a toy heat engine.  The source of energy in this phenomenon is a mystery to most students.  It is said that Albert Einstein and his wife Elsa were fascinated with this toy when they visited Shanghai in the 1920's. 

Web Resources:  The Engineering of the Drinking Bird, The Drinking Bird - Wikipedia
 

Very innovative creation, the bird will "drink" the water and keep moving. If you keep refilling the water, it will run forever! Experimented with one cup of water, it runs for 3 days non-stop until the water drop below the level it can dip on.