$6 Fuel Cell Spider

erco

I ordered one... it's um... educational, for my twins... magnesium + salt water makes enough electricity to power a motor. Pretty cool. I gotta be first to make a fuel cell robot. http://www.ebay.com/itm/191066634271

For $13, Jameco sells a little car with the same power source: http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2128340_-1

Gadgetman

I'm hesitant to call this a 'fuel cell' or even 'environmentally friendly'.
(Generally a fuel cell doesn't break down the catalyst)

They're Cool, though...

erco

Cool little kit, she works as advertised with nice leg animation. More science fair project than toy due to lots of prep & cleanup, though.

Partial assembly: http://www.youtube.com/watch?v=P6GJklJI6OI

First test: http://www.youtube.com/watch?v=YMGDq2_aizY