The US isn't just worried about terrorist bombings above-ground -- it's concerned about bombs below the waves, too. To that end, it's working with Saab on a remotely-controlled underwater robot, the Sea Wasp, that's designed to deal with improvised explosives. The machine (a smaller take on the existing Seaeye) uses a mix of sonar and a manipulator arm to find, move and sometimes disable explosives. Its party trick is its sheer maneuverability. It can hover in virtually any position, helping it dispose of bombs even when they're attached to a ship's hull.
This isn't just a far-off concept. Saab has delivered Sea Wasp prototypes to the FBI, South Carolina's counter-terrorism operations and the US Navy, and all three are conducting tests over the next 10 to 12 months. Underwater bombs aren't exactly a widespread problem at the moment, but this robot could easily justify its existence if it spares divers from swimming into harm's way.