Nanoelectonic devices have to have juice too, and thanks to a team at Harvard University, extraordinarily minuscule gizmos of the future could be powered via a "silicon nanowire that can convert light into electrical energy." The device itself is said to look much like a typical coaxial cable, but it's around 100,000 times smaller and shuns metal in favor of "silicon with three different types of conductivity arranged as layered shells." Reportedly, a single strand can output "up to 200-picowatts," which won't move much, but it could be just enough to run ultralow power electronics that could be worn on, or even inside, the body. Hopefully they'll have this all ironed out by the time we need a pacemaker.
[Image courtesy of Harvard]