Dr. Hibbert says that Hugo was "too crazy for Boys Town."
3rd segment title "Citizen Kang" is named in reference to this movie.
Nicholas Van Ryn says he could be hiding an insane twin brother in the attic, which is what the family do in "The Thing & I" segment.
The first segment's title is a pun on the name of this film.
there is a scene of an UFO crashing into the Capitol dome
End credits: "Norman 'Bates' McLeod"
Opening credits: "The Incredibly Strange Creatures Who Stopped Living and Became Ken Keeler, Dan Greaney, David S. Cohen"
End credits: "Domi 'Blackula' Braud"
Cartman gets his own civilization of little creatures who see him as their god, then Butters goes into great detail about how they already did that on this episode of The Simpsons
Lisa becomes mistaken for God by a tiny civilisation just like in this episode of the Twilight Zone