No Mormonism?! That was my first thought!
I always found Norse myths to be quite fun, so that’s what I voted for.
I just realized OP forgot about cargo cult. That is a fun one.
Another fun one was Frederick Lenz. He was a new age leader who told his female followers if they had sex with him it would raise their vibrational frequency to a higher level and spiritually evolve them.
Does that mean it’s doubleplusgood?
Same here. The people themselves are fine,* but the closer one looks into their religion, the sillier it gets.
- My sample groups are several relatives, and many former clients.
Depends. LaVeyan Satanism is more of the “too cool for school” variety. It shares lots of things, if not politics, with Objectivism. Speaking of which, that’s kind of a religion.
I prefer the Prince Philip movement. Yes, after the Queen’s husband, who is worshiped by people of whom he has probably made racist comments about.
That was South Park’s basic commentary (and I assume the Book of Mormon, though I haven’t seen it). Nice people, earnest, with some ridiculous premises. So they got off very easy, considering how much worse it could be.
Some of the literature from Jehovah’s Witnesses can be right up there in the entertainment category.
Some of their missionaries came to my door once, peddling this book for just $3:
Revelation It’s Grand Climax At Hand!
It’s a chapter-by-chapter, verse-by-verse detailed explication of Revelation, heavily illustrated as only JW can do!
I bought it on the spot, of course!
If you liked all that Greek mythology, with the epic battles of the gods and such, you’ll love this! Multi-headed multi-horned monsters fu! Apocalyptic horsemen spewing swords from their mouths fu! Blood spilled upon the earth fu! Angels going mano-a-mano with the great serpent fu! Satan in chains for a thousand years fu! Whore of Babylon fu! It’s all there!
The existence (and reported growing popularity) of snake-handling Pentecostalism alone makes Christianity deserving of my vote.
Church of the SubGenius.
The original religious satire religion.
Get some Slack in your life.
J. R. “Bob” Dobbs will show you the way. Or sell you something. Or both!
The aforementioned Discordianism is about 16 years older, though as I noted “Bob” is the Most Holy.
Learened something new today. 
Seems like maybe you’re more of a natural for the SlowGenius offshoot sect. 
Or the Fail to read for content set… Oh, wait… 