The Office of Naval Research is looking for a way to autonomously scrub a vessel's hull on a regular basis. Doing so not only makes them look darn pretty, but scraping off barnacles improves a ship's speed and dramatically reduces fuel consumption.
One solution is the Bio-inspired Underwater Grooming (or BUG) robot. It uses suction to keep itself stuck to a vessel, and features biofilm detectors and flourometers to help it plot its path toward grime and buildup while underwater. A unit like the BUG could clean a vessel during its voyage, which would not only keep it running efficiently, but would also save the Navy some dough on maintenance and reduce the fleet's carbon footprint overall.
The Navy hopes to have BUGs crawling all over its vessels by 2015.