The Simpsons (1989)

Cape Feare - S5-E2

Trivia: Bob's prison number is A113. This number is often used as by alumni of California Institute of the Arts (most famously by Brad Bird, in his Pixar films and episodes of the Simpsons he was involved in, such as this one) - it's the number of one of the classrooms.

The Principal and the Pauper - S9-E2

Trivia: Martin Sheen was chosen to voice the "real" Seymour Skinner because the producers had admired his role in Apocalypse Now, and thought his voice would be appropriate for a Vietnam veteran.

Lisa the Vegetarian - S7-E5

Trivia: Paul McCartney agreed to guest star on the condition that Lisa's conversion to vegetarianism remain permanent. This is one of the few points of continuity that has been strictly adhered to.

Tree House of Horror IV: The Simpson's Halloween Special IV - S5-E5

Trivia: When Marge asks Bart to explain how scary the episode is, she mentions the "War of the Worlds" broadcast on NPR. Narrated by Orson Welles, that radio serial was so chilling, a number of listeners actually believed Earth was under attack.

Tree House of Horror XII - S13-E1

Trivia: In "House of Whacks", the murderous house is disengaged when its British charm unit is removed; Pierce Brosnan, the personality whom the family had chosen for the house, is actually Irish.

Trivia: One of the sliest jokes in the series' entire run is the name of talk-show host Opal's boyfriend, Straightman. Steadman Graham, the longtime beau of Oprah Winfrey (on whom Opal is based), is rumored to be gay.

Mommie Beerest - S16-E7

Trivia: When Homer sees Moe as the little bird in the cuckoo clock, it keeps repeating "cuckold" instead of its customary cuckoo call. Homer then asks, "Whats a cuckold?" The term is generally applied to a husband whose wife is sleeping with other men. Perhaps fitting, as Homer suspects her of having an affair. (Source).

Lummie

The Italian Bob - S17-E8

Trivia: This episode contains pictures of Peter Griffin from Family Guy & Stan Smith from American Dad.

When You Dish Upon a Star - S10-E5

Trivia: Another thing "The Simpsons" predicted: Towards the end of this episode, a sign outside of a film studio shows the 20th Century Fox logo with "A Division of Walt Disney Co" written under it. Nineteen years after this episode aired, Disney purchased many assets from 20th/21st Century Fox, including "The Simpsons."

Phaneron

Trivia: Although Marge's sisters, Patty and Selma, are identical in appearance, there is an easy way to distinguish the two: Selma has an "M" in her name, and her hair is parted in the shape of that letter.

Trivia: Dan Castellaneta and Hank Azaria both voice about ten regular characters, with Azaria contributing another ten recurring, and Harry Shearer voices twelve regulars.

Sideshow Bob's Last Gleaming - S7-E9

Trivia: When we are first introduced to Sideshow Bob, he is building a ship out of sticks. Look at his name tag. It says A-113 on it. A-113 is the classroom number used by character animation students at CalArts, frequently used as an inside joke by graduates, right the way up to Pixar movies.

Trivia: In a recent episode (I saw it when it premiered on 5/17/09) the Odgenvillians move into Springfeild, then are forced out. When Lenny and Carl go on the chair attached to balloons, you can see the house for Pixar's latest film, Up, in the background.

How I Spent My Strummer Vacation - S14-E2

Trivia: At the Rolling Stones' fantasy camp, Mick Jagger's diploma from the London School of Economics is on the wall in his office.

Hello Gutter, Hello Fadder - S11-E6

Trivia: When Homer asks Lenny and Carl, "Are poo and ass taken?" Jacque, Marge's ex-boyfriend along with Homer's ex, Lurleen Lumpkin, pass by together in the background.

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."

Phaneron

Homer Loves Flanders - S5-E16

Trivia: As Flanders drives to get away from Homer, Homer runs after him with putters in both hands. As he does, he mimics the actions of the T-1000 in Terminator 2, who was trying to get John Connor.

Mr. Plow - S4-E9

Trivia: After Homer rescues Barney, the sun shines through the clouds and melts the snow. In a quick shot, as two snowmen are melting, the one with spectacles melting is a quick nod to Raiders of the Lost Ark, when the Nazis melted after opening the Ark.

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.

Trash of the Titans - S9-E22

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"