Mystery Science Theater 3000
A much loved tv program that ran on various channels between 1988 and 1999, produced by Best Brains, Inc. The basic premise of the series was that a human host and two robots were held prisoner on a satellite by mad scientists and forced to watch bad movies, which they would make fun of. Much has been written about this series elsewhere.
Actors included Joel Hodgson, Mike Nelson, Mary Jo Pehl, Bill Corbett, and Bridget Jones + others, with Paul Chaplin participating as a writer of the non-werewolf variety. The program was shown most recently on SCI FI Channel, being by that august broadcasting body of great distinction first canceled, and then no-longer-run-even-in-reruns. (For more on this sequence of events, see Bonnie Hammer.)
While Caption This! did not become Mystery Science Theater 3000 Presents Caption This! until a few months (weeks?) after its introduction on scifi.com, the staff of MST3k had very little to do with CT, and the capping community has gone on without SFC or MST, the show still occupies a special place in the capper community. While not all cappers are msties, and most msties aren't cappers, a majority of cappers came to CT! via its link to MST. Many of the cappers running gags were "inspired" by MST.
The annual Thanksgiving "Turkey Day" marathons of MST from its days on Comedy Central have been adapted by two of the biggest present day capping venues. Inventing Situations shows the cappers' hubris by running screengrabs from original versions of films that were featured on MST during the annual Bake Your Own Turkey Day weekend and imagining that the cappers might successfully add onto what the Brains did. Meanwhile, Glitter's Cap-Page Board manages to show even more hubris, running actual episodes of MST for capping around Thanksgiving.