DNA Sans, a typeface / character set of self-assembled DNA strands that have been shaped into pixel-like blocks. I know where I’m stashing my next steganographically-hidden secret message! (Or maybe this could be used as graffiti for the Fantastic Voyage crew?)
Moving things (very, very, very tiny things) using nothing but photons. Not immediately useful given the scale, but this is a first and could have applications in nanoelectromechanics and biology. Originally this same principle was thought to be what powered the nifty Crookes radiometer (that black-and-white vaned vacuum bulb thing that’s now usually sold as a novelty desk toy), but that device is actually moved by thermal transpiration or temperature differences.
(If the above link is behind a paywall for you, you might try the basic Nature writeup instead)