Bill Cosby joined the U.S. Navy, serving at the Marine Corps Base Quantico, Virginia, Naval Station Argentia, Newfoundland and at the Bethesda Naval Hospital in Maryland. While serving in the Navy as a Hospital Corpsman for four years, Cosby worked in physical therapy with some seriously injured Korean War casualties. Comedian Bill Cosby is recognized as an Honorary Chief Petty Officer, during a ceremony in Washington, on Thursday, Feb. 17, 2011. (AP Photo/Jacquelyn Martin)