rec.humor.funny
Usenet's moderated joke group, which for a while had more readers than almost anything else on the network.
Brad Templeton started it in 1987 as a filtered version of rec.humor, where anyone posted anything. Here only jokes the moderator himself found funny got through, a couple a day. It worked: rec.humor.funny sat at the top of the readership surveys for years, and for plenty of people it was the only reason to open a newsreader.
In 1988 an ethnic joke drew protests, and the University of Waterloo stopped letting the group run through its machines. Templeton moved it and soon used the same setup for ClariNet, a paid news service delivered over Usenet. The group thereby became an early case of a question nobody has settled since: who answers for what a moderator chooses to publish?