This video camera is powered by light
No, you haven't stumbled across an internet video from 1997 -- that's the output of one of the cleverest cameras you'll see in a while. Columbia University researchers have developed a self-powered camera whose pixels both record light and turn it into electricity. The trick is the use of photodiodes (which are common in both cameras and solar panels) that are permanently set to collect energy, not simply conduct it.
As you can see from the blurry, goofy animation above, the existing technology won't compete with the camera in your phone, let alone a pro DSLR. Columbia's prototype captures just 1,200 black-and-white pixels, and it needs a lot of light just to keep running. Even so, it's promising. If scientists can refine the technology to work at multi-megapixel levels, you could see cameras that last a long time on battery, and might not need a battery at all.