The Church of the Flying Spaghetti Monster, after having existed in secrecy for hundreds of years, came into the mainstream just a few years ago.
With millions, if not thousands, of devout worshipers, the Church of the FSM is widely considered a legitimate religion, even by its opponents – mostly fundamentalist Christians, who have accepted that our God has larger balls than theirs.
Some claim that the church is purely a thought experiment or satire, illustrating that Intelligent Design is not science, just a pseudoscience manufactured by Christians to push Creationism into public schools. These people are mistaken — The Church of FSM is legit, and backed by hard science. Anything that comes across as humor or satire is purely coincidental.