#4 "The French Mistake," Supernatural

In this ultimate meta episode, Sam and Dean were transported to a world where they were Jared Padalecki and Jensen Ackles, actors on a TV show called Supernatural. The absurd level of inside jokes like the YouTube clip of Jensen on Days of Our Lives and the brilliant way they actually killed off co-star Misha Collins and creator Eric Kripke, among others, was perfectly zany.