Scientists in Singapore have invented a pee-powered battery.
They claim that this urine-powered battery was invented to create a low-cost, self-powered diagnostic kit to detect diabetes and other illnesses.
I suspect they just wanted to invent something that you could pee on.
In other pee-related news...
A restaurant in China was raided for selling the meat of endangered tigers on its menu. However, it turned out that what they were listing as tiger meat was actually really just donkey meat marinated in tiger urine.
Which I always guessed would taste just like chicken. Link