What if you could turn the music down on your phone by just waving your hand? That's the idea behind AllSee, a new gadget under development by computer scientists at the University of Washington. Built by the same guys who created the gesture-recognition in the Galaxy Nexus, the tiny sensor works completely different than the feature in devices like the Galaxy S5 that require the use of the forward-facing camera. Instead, AllSee uses TV signals to not only help it recognize gestures, but also as exceptionally efficient source power. That means it doesn't need a battery to operate and can see your movements even when your phone is out of sight in your pocket -- pretty awesome.