There is a video out there in Youtube claiming to charge an iPod through an Onion. The video had been viewed 3,868,695 times and counting, and it had attracted 22375 comments so far! See the video yourself:
Not a great Idea?
Yeh, it seems. Some people in India are actually using COW DUNG not only to charge and power up their mobile devices, but to illuminate their surroundings during night hours! You can read about this in BBC Hindi article here.
Powering UP with Cow Dung.