The Greatest American Hero was a TV show in the 80s. Starred William Katt and Robert Culp.
It was about a regular guy (a teacher) who found a suit that was from outer space. When he'd put the suit on it made him a super hero. He was kind of a bungling super hero because he never really mastered the powers it gave him.
Anyways, I liked the show and the theme song. Here's the song: