John Limbert stepped down Friday as head of the State Department's Iran desk. In 1979, Limbert was one of 52 Americans taken hostage during the Islamic Revolution. He was held for more than a year. Brad Horn/NPR hide caption

itoggle caption Brad Horn/NPR

One of the negatives discovered by Rick Norsigian. Courtesy Rick Norsigian hide caption

itoggle caption Courtesy Rick Norsigian

Ashton Stark stands next to his 1972 Volkswagen Beetle, which he converted into an electric car. Courtesy Noel Stark hide caption

itoggle caption Courtesy Noel Stark

Creek County in Oklahoma is so big, responding to a call can sometimes take a bit of research for Cpl. Allen Harwood. Gail Banzet/NPR hide caption

itoggle caption Gail Banzet/NPR

Staff members at the Army Experience Center in Philadelphia demonstrate the Humvee interactive simulator in 2009. Matt Rourke/AP hide caption

itoggle caption Matt Rourke/AP