Recent research over the past few years have shown that light can be converted at least partially into motion, or more specifically vibration. While this seems innocuous, it could open up new ways of performing actions in optical microcircuits.
Physicists at Caltech and Duke University have shown that light could be made to make glass vibrate. They were even able to store a pulse of light traveling down a fiber as a vibration and then release it nanoseconds later.
One application would be to have optical microchips where vibrations or microwaves control high-frequency optical signals or the reverse. Of course, science has a strange way of spawning applications that were not envisioned at the time of discovery.