Imagine a submarine. Now shrink that down to one-tenth the size of a human hair. It's not science fiction. Scientists recently made these tiny "microsubmarines" a reality. According to the American Chemical Society journal ACS Nano, scientists have created the first ever self-propelled "microsubmarines" able to pick up and transport droplets of oil from contaminated waters. These tiny machines could play an important role in cleaning up oil spills, like the 2010 Deepwater Horizon incident in the Gulf of Mexico.