The Church of the SubGenius

A parody religion built around a pipe-smoking clip-art salesman called J. R. "Bob" Dobbs, selling eternal salvation or triple your money back, and preaching Slack.

The purest specimen of the American photocopier underground, and a genuinely useful idea inside the joke: Slack — the thing you are owed, that the world is organised to take from you, that cannot be earned by working harder. Half the people who paid for ordination were laughing. The other half were not, and the church has never clarified which it wanted.