The end of the episode mimics the end of X-Men where Magneto is kept in a glass-type prison.
The episode is based on a 25 year old script written in 1990 by The 40-Year-Old Virgin (2005) Writer & Director Judd Apatow
Don Bookner likens rooting for Homer to rooting for the Cubs, hoping they'll make it all the way, "then you realize they never, ever will." Late the following year, the Cubs DID make it all the way to winning the World Series, their first victory in the World Series in more than 100 years.
When leaving the circus tent, the Simpsons walk down the midway, lined with amusement booths named after projects Judd Apatow is known for: Freaks and Geeks, Drillbit Taylor, Funny People, Fuperfat (Superbad), and The 400 Year Old Virgin (40 Year Old Virgin) Fuperfat and the 400-Year Old Virgin are the only ones that are parodies while the rest are real.
Hypnotized by Sven Golly, Cletus claims to show a proof of Zorn's Lemma, which is a real and important result in the mathematics of set theory.