 In the episode "The Honking" Bender sees a computer code of a long  string of ones and zeros written on a wall, which doesnt make any  sense. He then sees it reflected in a mirror, and it translates into  "666", which scares him. This is a reference to  _Shining, The (1980)_ (qv) where the odd word "REDRUM" becomes  "MURDER" when seen in a mirror.