The “Flying Spaghetti Monster” was born as an inept parody of intelligent design arguments.
About this, philosopher William Lane Craig is right on the money.
The FSM is more than this, though. It is thought by many village-atheist-type young males (roughly 12-29) to be an oh-so-clever-and-naughty parody of monotheism in general, apart from any design-creation controversies.
The thing is, the FSM is not clever – only naughty – or at least, potentially so, if people care enough to be offended by it (which I do not recommend). Really, the only amusing thing about it is how amused these folk are with themselves, as they think they’ve somehow pulled the pants down on believers in God.
But the joke’s on them.
Here are two differences between God and the FSM: (1) Many of our greatest scientists and philosophers have believed in God (examples: Newton, Descartes) – either on the basis of one or more arguments or based on his being the best explanation for certain facts vs. no such people re: the FSM, (2) countless seemingly sane people claim to have experiential evidence for the existence of God vs. none for FSM.
Now these facts don’t show that God exists or that it is reasonable to believe in God. But it does show that it is reasonable to investigate the existence of God and not give another two seconds of thought to the FSM.