He eventually found a mentor in Johnny Carson, who often tapped him to guest host "The Tonight Show," and ultimately landed his own short-lived TV gig -- albeit in the morning -- with "The David Letterman Show" (1980).
But the funnyman's talents shone most brightly after the sun went down as host of "Late Night with David Letterman" (1982-93) and "Late Show with David Letterman" (1993-?), a pair of Emmy-winning programs that would add "Stupid Human Tricks" and Letterman's signature "Top Ten List" to the annals of American pop culture. He is also somewhat infamous for hosting the Oscars in 1995.
After realizing that their beloved boob tube is gone, couch potatoes Beavis and Butt-head (both voiced by creator Mike Judge) set off on a cross-country expedition that takes them from Las Vegas to the nation's capital. Along the way, they're mistaken for hit men and get caught up in a weapons-smuggling conspiracy as a gaggle of mobsters and lawmen shadow the two morons. Celebrity voices include Cloris Leachman, Robert Stack and David Letterman.