The Episode: Season 4, Episode 15 (I Love Lisa) The Gag: One of the most memorable moments in the history of the show has Ralph Wiggum despondent over receiving no Valentine's Day cards. Lisa, feeling bad for him, gives him one, with the hilarious inscription, "I choo-choo-choose you", which seems to shock and bewilder Ralph. It's a sweet and funny moment and one of the few on this list which doesn't exploit Ralph's idiocy. Added trivia: the episode is based loosely on an incident in showrunner Al Jean's life, where a girl gave him this card and, years later, made him wonder whether the girl actually liked him or not.