Ed McMahon

Ed McMahon was a beloved American institution, having made his living almost entirely by heartily agreeing with Johnny Carson and/or delivering oversized novelty checks to the doors of unsuspecting people. He lost his pre-dead status in 2009, and is buried with Johnny Carson.
His original name was Dick Clark, but he changed it to avoid confusion with the Dick Clark Five.
A fictionalized version of McMahon is currently being played by Andy Richter, Conan O'Brien's own right-hand yes man, on the gripping TBS drama Conan.