This is yet another of those gadgets that has me wondering how on earth it was invented. These batteries from NoPoPo are rather pocket friendly, and environmentally friendly too, as you can reuse them again and again. By filling them up with your own wee.
One of these urine powered batteries, available in AA or AAA, is able to power a flashlight for up to 20 hours. You 'recharge' the battery by using the included pipette to refill it with urine and you're all set. You can also use beer, saliva and cola among other, if the idea of touching your own waste isn't your cup of tea. Disappointingly enough, they're only available in Japan as yet.
[Source]
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