10. 'Mork & Mindy' (1978-1982)
A true force of nature — actor Christopher Reeve, who met him in the early 1970s at Julliard, once described him as "like an untied balloon that had been inflated and immediately released" — the late Robin Williams brought such a quirky intensity to his free-associative stand-up routines that casting him as an errant extraterrestrial in made perfect sense. (Producer Garry Marshall once cracked that Williams was the only real alien who auditioned for the role.)
A spin-off featuring the comedian's one-off character from Happy Days, this show sent Williams' native of the Planet Ork native back to Earth in an egg-shaped spaceship and dropped him in modern-day Denver. Though the scripts generally centered around Mork's struggles to understand the ways of Earthlings, they were largely written to allow ample room for Williams' wacky improvisations. The sitcom rocketed Williams to stardom; the catchphrases "Shazbot!" and "Na-Nu Na-Nu" became so ubiquitous in 1979, even AC/DC frontman Bon Scott could be heard muttering them at the very end of the Highway to Hell LP. It may have cleaned up his stand-up act, but the show also paved the way for his stream-of-conscious patter to hit a much bigger mainstream audience.