Well, one of my favorites will always be "Dances with Smurfs". I like how Cartman was all up against Wendy for being class President and using the Smurfs to turn kids against her, but at the end, she played along and sold Cartman's rights for his story to James Cameron and turned it into "Avatar". I almost died laughing with it. xD
Well, I'm watching videogame parodies on Youtube right now. =D