The Curiosity Company Vanity Plate is an extremely obscure throwback to "A Study in Wet", a trippy experimental short film by Matt Groening's late father Homer.
In the episode "Proposition Infinity", you can see Gay Robot from Nick Swardson's Pretend Time dancing in the crowd.
The episode "Love and Rocket" is a series of shout-outs to 2001: A Space Odyssey from Bender singing "Daisy Bell" while on a date with the Planet Express ship's new sentient persona to them visiting the zoo and seeing tapirs.
"Lethal Inspector" does an impressive one without ever outright explaining the joke. Hermes has a cubicle next to the "center square", a sassy gay man who eventually has a large red "X" appear on his desk. It's Paul Lynde, of course, but neither his name nor Hollywood Squares are ever mentioned.
Professor Farnsworth is named after (and in-universe descended from) Philo T. Farnsworth, the inventor of electric television.
The episode "Fry and the Slurm Factory" is not only an example of Charlie and the Chocolate Parody, but also shares elements with the B-movie The Stuff. Both the film and the episode feature a highly addictive substance that becomes a huge marketing success and is discovered to be something else (alien fluids/some kind of sentient goop); in both the processing plant/factory is destroyed at the end. There's also the exchange "Soon enough!"/"That's not soon enough!" that sounds like the "Enough is never enough!" marketing claim of the Stuff.
Also, in the Simpsons episode Mayored to the Mob, Üter wears a Futurama shirt (which was changed to a Star Wars shirt in reruns for reasons unknown). In an episode of Futuramanote season one's "A Big Piece of Garbage, Bender eats the shorts off a Bart Simpson doll (an early 1990s one that had a blue shirt instead of an orange-red one).
Un-Cancelled: Once upon a time in 1999, FOX had been giving the show an inconsistent airing time after season one, and the show was frequently pre-empted by football games. Once, they didn't even bother with the football game and just ran commercials for 10 minutes where the first act should have been. For obvious reasons, this led to disappointing viewer turnout and ratings, despite the pilot episode ("Space Pilot 3000") being the highest rated premiere in the history of the FOX Network. Soon, it was announced that FOX had cancelled the show after the episode "The Devil's Hands Are Idle Playthings", which was written to serve as a potential Grand Finale. Reruns soon went to Cartoon Network's [adult swim] line-up note (along with Family Guy, which was also canned after three seasons of mediocre ratings), and the episodes actually got more viewers than the first-run episodes on FOX now that the show had a consistent time slot and no pre-emptions. The season set DVDs added to Futurama's popularity, as people now got the chance to see what they were missing without the inconveniences of television (commercials and pre-emptions). Because of this, Matt Groening and his crew for Futurama created four direct-to-DVD movies (Bender's Big Score, The Beast with a Billion Backs, Bender's Game, and Into the Wild Green Yonder), which were again designed to serve as a finale if needs be. (Into the Wild Green Yonder ended with everyone in the Planet Express Ship flying into a wormhole, with heavy implications that they're never going to come back to Earth). Comedy Central also starting airing the movies and the regular series episodes after Matt Groening turned down the chance to have the show renewed on Cartoon Network and Cartoon Network lost the syndication rights to the show in 2007. Comedy Central subsequently ordered new episodes of the show. Despite some complaints about the Comedy Central episodes being inferior to the FOX episodes due to whatever reason the fanbase has (no character empathy, lack of believable storylinesnote never mind that this is a sci-fi cartoon, indulging in vulgar humor, etc), Futurama enjoyed a good four years on Comedy Central. However, the good times were not to last. In April of 2013, it was announced that Comedy Central was pulling the plug on the show, making the episodes in the second half of the show's seventh season (tenth, if you go by broadcast history) the final episodes ever aired (the final episode "Meanwhile" aired on September 4, 2013). Despite this, Matt Groening is looking to pitch the show to another channel and hopefully revive the series once again, and he is planning on a Futurama-Simpsons crossover where Bender is sent back to the past to kill Bart for a future crime that will either air on the 25th season or the 26th.
Viewers Are Geniuses: Turanga Leela is named after the Turangalîla Symphonie — a piece of orchestral music by Olivier Messiaen. If you knew of the piece or of the composer without having to check Google, you are a devoted classical music fan and/or an academic.
Lots of jokes rely on the viewers being smart enough to understand it, especially the math, engineering, and science jokes, which most viewers wouldn't get unless they were in college or taking Advanced Placement high school classes.
What Could Have Been: Eric Rogers revealed that they considered making a claymation segment for Reincarnation, but didn't due to time constraints and money issues.
Originally, Futurama was going to be called either Aloha Mars! or Doomsville, and center on a dystopic future ruled by an elderly businesswoman named Mom and her surly, cynical delivery boy named Curtis.
Phil Hartman was supposed to voice Zapp Brannigan, but the death at the hands of his wife ruined any chance of that. In memory of him, Curtis Fry was renamed Phillip J. Fry and Billy West voiced Zapp Brannigan with the same kind of smugness you'd expect from a jerkass Phil Hartman character.
Fry and Leela were originally supposed to be played by Charlie Schlatter (from 18 Again!, Diagnosis: Murder, and Loonatics Unleashed) and Nicole Sullivan (Bizzy from the cartoon version of Baby Blues and best known as the Vancome Lady from MADtv) respectively.
An old character design for Bender shows that he had antennae where his ears are.
Hermes was originally going to have the Brain Slug on his head throughout season 2 instead of a single episode.
The MovieBender's Game practically canonizes Walt, Larry and Igner's ages when Nibbler says "It was 36 years ago... now" when Mom started drilling for Dark Matter with the intention of selling it. With their ages being only a couple of years apart and Igner being unborn and only just concieved at the time (Mom didn't appear pregnant in flashbacks)...
She had to have been pregnant (but not showing) in the scene where she leaves Farnsworth, because we know who Igner's father is.