6. 'Mork and Mindy'
If The Flintstones could introduce an alien character into the mix (long live the Great Gazoo), why couldn't Happy Days get a little intergalactic as well? The through-the-roof popularity of Mork's first appearance on TV's Fifties nostalgiafest practically demanded he get his own show, and after the series started airing in 1978, you could not escape the sight of people wearing rainbow suspenders or yelling "Shazbot!" It was the public's first introduction to Robin Williams' manic, machine-gunning style of humor, and the role made him a huge star; even when things starting getting ridiculous around the end of the run (Jonathan Winters as a Benjamin Button-ish baby Orkan?), the actor's infectious energy always kept thing moving at warp speed. DF