The Longreach Buoyancy Deployment System is a gadget in development that fires a buoyant life preserver at people stranded in the water up to 150 meters away:
Longreach is also equipped with Para-Flares for night-time Illumination. Longreach is designed to be simple to manufacture and easy to handle. Ideally used by emergency services personnel or a ship’s crew, Longreach has the potential to significantly reduce the number of drownings at sea.
Video at the link.
http://www.jamesdysonaward.org/Projects/Project.aspx?ID=1010&RegionId=0&Winindex=5 via GearFuse | Photos: Dyson Award
After over forty years, it's about time someone tried to make that work...