Marge vs. the Monorail - S4-E12
Trivia: Conan O'Brien, who wrote this episode, did a live rendition of "The Monorail Song" at the Hollywood Bowl in 2014 with the Hollywood Gay Men's Choir and Hank Azaria. He dedicated the performance to Phil Hartman.
Trivia: Ned Flanders inspired the term "Flanderization", used to describe TV characters who started off with a few personality traits, but are now dominated by just one. In earlier seasons, Ned was a polite, respectful man who attended church, but was not especially pushy about religion. He and his family became more strictly Christian, portraying a "Bible-beater" stereotype.
Trivia: For the chalkboard gag in the opening theme, Bart is writing "I am not a 32-year-old woman." Nancy Cartwright, the actress who does his voice, was 32 years old at the time.
Trivia: The joke about Martin having an alternate version of 'Return of the Jedi' where Chewbacca is Luke's mother is based on one of Mark Hamill's anecdotes. During the filming of ROTJ he was informed Lucas had something important to tell him in private, which he'd previously done to drop the twist that Vader was Luke's father. This caused Hamill to quip "Oh no, is Chewbacca going to turn out to be my mother?" He was relieved when the actual revelation was that Leia was Luke's sister.
Trivia: Marge's hairstyle in this episode is the Rachel, popularized by Jennifer Aniston on Friends.
Trivia: In the opening sequence post Feb 2009, Marge can be seen placing items on the checkout. These include the detergent Mr Sparkle from Season 8 Episode 22, In Marge We Trust, and some Tomacco juice from Season 11 Episode 5, E-I-E-I - (annoyed Grunt). (00:00:25)
Dude, Where's My Ranch? - S14-E18
Trivia: At the beginning of this episode, Homer writes his own Christmas carol after being barred from performing traditional carols because of copyright issues. Around seven years after this episode aired, the musical artist Usher was ironically accused of plagiarizing one of the tunes Homer was working on with his song "OMG."
Trivia: Sideshow Bob's passion for singing is a dimension to the character that was uniquely Kelsey Grammer's, stemming from his own personal history of singing standards on the set of Cheers.
Trivia: The musical number "The Garbageman Can" was a nod to musical number "The Candyman Can" in the 1971 classic "Willy Wonka and the Chocolate Factory"
When You Dish Upon a Star - S10-E5
Trivia: At the end, Homer prank calls the "old lady from Titanic." This is Gloria Stuart, who tied with Kim Basinger (one of the main guest stars of the episode) for the SAG Award for Best Supporting Actress.
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.