Japanese scientist has invented Water Battery
A Japanese scientist has invented a new kind of water-powered battery which can be recycled several times - and it's as powerful as a conventional battery. He said, if mass-produced, it could cost as little as a tenth of the price of conventional batteries.
Here you can find some video on EuroNews site.
"This battery can never be activated without water. It can keep for many more years than normal batteries. It could be an ideal tool in disaster prevention. ... For example, when you get lost on a mountain, by licking its surface you could get electriciy for a flashlight or radio."
Batteries Powered By Water [Reuters via Engadget]