Engineers at Rensselaer Polytechnic Institute have developed a flexible, paper-like battery that can function in temperatures up to 300 degrees Fahrenheit and derive power from human sweat…and blood. While this might sound strange, the idea is that you could use them to power small implanted devices, like pacemakers, and the electrolytes found in blood, urine or sweat could be used to activate the battery.

But the coolest feature may be the battery’s structure. It’s 90 percent cellulose, which means it’s basically a piece of paper. The difference is that this paper is laced with a carbon nanotube skeleton. The nanotubes conduct electricity through the device, and allow it to be bent and twisted without breaking. Best of all, in the when-does-this-thing-get-into-our-gadgets sense, is the fact that it may end up being cheap to produce, since the materials are inexpensive.—Gregory Mone