Watched Underwater by a Robotic Tuna

When you think of autonomous, unmanned spy vehicles, you probably imagine the telltale shape of a small aircraft overhead, and the suspicious sound of whirring propellers. Spy vehicles, however, aren't just for the sky anymore. The U.S. Navy has funded the development of an autonomous, unmanned vehicle shaped like a fish and capable of covering up to three times the distance of a typical UAV using the same battery. It's called GhostSwimmer, and it'll be entering