I view the following as my lifetime contribution to religious belief in this day and age (cribbed from a discussion on Facebook -- all statements are my own, although some were, in part, inspired by comments from others):Cthulhu is to the Flying Spaghetti Monster as Satan is to God.
Cthulhu has noodly appendages, of a sort, as well, and like all the Elder Gods he has a ravenous appetite. Cthulhu's preferred attempt to defeat the FSM is to eat him whole. Logically, this will only result in his own self-immolation when he bursts from eating more than his stomach can hold as the FSM is the metaphysical equivalent of a never-ending pasta bowl. However, as the Elder Gods are limitless in their appetites, the result is actually a draw. Nonetheless, I like the idea that the opposing parties in my religious faith are truly equally matched -- it makes things more interesting.
I know there's nothing in The Gospel of the FSM to confirm any of this, thus making it a heresy. However, the awesome thing about the Church of the FSM is that it blissfully ignores heresy.
* It should be noted that in "Heartattack and Vine" Tom Waits sang, "Don't you know there ain't no devil, there's just God when he's drunk." Ergo, one can easily argue that Cthulhu is just the FSM on a bad acid trip (an argument I wish I thought up).