since we had a 'favourite simpsons episode' thread, this seems to be the natural successor.
like the simpsons there are so many to choose from, but these are probably my top three:
mecha-streisand--robert smith and sidney poitier saving the planet from the giant streisand. (whenever i would tell one of my cure-loving students how NO are better the cure, his reply was always, 'perhaps, but robert smith did save the world from barbra streisand, you know.)
cartman wants to meet more 'mature' friends and sends out an IM saying that a young boy seeks friendship with older men. he gets message after message and thinks there are a lot of men who are keen on becoming 'friends' with a pre-pubescent boy. he eventully joins NAMBLA at the suggestion of the professor, where he's told he'll meet some friendly older men. it turns out the professor was referring to the north american marlo brando look-alikes.
currently my favourite: kenny gets to level 50 (?) playing the game 'heaven vs. hell' on his new PSP and god arranges for kenny to die because he has defeated all possibile scenarios in the upcoming war between the real heaven and hell. he is heaven's 'keanu reeves.' just as he is about to control the legions of god's army, he's brought back to life by the doctors, but in a persistent vegtative state. god's angels wonder what is wrong with these people who want to play god by keeping kenny alive, thereby putting the kingdom of heaven at great risk. brilliant!