!![[Franchise/TheHitchhikersGuideToTheGalaxy General franchise]] trivia:
* AdaptationSequence: Radio Serial > Books > TV Series > Adventure Game > Movie
* BeamMeUpScotty: Say it with me, people. It's "The Answer to the Ultimate Question of Life, the Universe and Everything". Not the meaning of life.
* TechnologyMarchesOn: Digital watches sure are a neat idea, huh?
* TropeNamer:
** BitsOfMeKeepPassingOut
** DeconstructorFleet (pun on Vogon Constructor Fleet)
** FutureImperfect
** GargleBlaster
** InsignificantLittleBluePlanet
** LetsMeetTheMeat
** PuffOfLogic
** RealityIsOutToLunch
** SoLongAndThanksForAllTheGear
* UnfortunateName - Slartibartfast. Adams wanted him to have an immense sadness, so gave him a terrible name. He started with [=FartyFuckBalls=], and mutated it until it sounded rude without actually being rude.

!![[Film/TheHitchhikersGuideToTheGalaxy Movie]] trivia:
* RetroactiveRecognition: The four leads are Creator/MartinFreeman, Mos Def, ZooeyDeschanel, and Creator/SamRockwell (the GenreSavvy RedShirt from ''Film/GalaxyQuest''.) We later see John Malkovich and [[Film/{{Underworld}} Victor]] / [[Franchise/PiratesOfTheCaribbean Davy Jones]]
** [[Film/ShaunOfTheDead Shaun's Dad]] and [[{{Film/HarryPotter}} Rufus Scrimgeour]] are Slartibartfast!
** The TV version's Arthur Dent as the recorded message from Magrathea.
* HeyItsThatVoice: Marvin has the same voice as [[{{Dogma}} the Metatron]] and [[Film/DieHard Hans Gruber]] and [[Film/HarryPotter Snape]]. The Guide is voiced by StephenFry. Deep Thought is voiced by Creator/HelenMirren.
** Marvin has the voice of Snape and the body of Flitwick.
** BillBailey as The Whale.
** [[Film/WithnailAndI Uncle Monty]] is Jeltz, [[Recap/DoctorWhoS31E3VictoryOfTheDaleks Winston Churchill]] is Kwaltz, and the rest of the Vogons are Series/TheLeagueOfGentlemen!

!![[Radio/TheHitchhikersGuideToTheGalaxy Radio]] trivia:
* Slartibartfast is not named for the majority of the episode he first appears in. WordOfGod explained that it was a joke at the expense of the woman who had to type the scripts - that she'd typed this name a dozen times and he simply said 'My name is not important'.
* The seventh episode was originally broadcast on 24 December 1978. Consideration was given, partly due to the date and partly due to the fact that all the plot threads had been tied off at the end of episode six, to making it a stand-alone Christmas special in which Marvin would have been both figuratively and literally the star (of Bethlehem), and by participating in a nativity scene would be cured of his depression. In the end they made it a normal episode, devoted to untying enough plot threads for the series to continue.
* HeyItsThatVoice: In the recent radio adaptations we have Creator/ChristianSlater as Wonko the Sane, Jackie Mason as The East River Creature and StephenFry (again) as Murray Bost Henson. The gent who would later become familiar as the voice of WesternAnimation/DangerMouse, David Jason, was the Golgafrincham "B" Ark Captain in the primary phase series.
** And Jim Broadbent played one of the complaining philosophers and one of the gun-happy cops on Magrathea.
* Creator/{{Hipgnosis}}: Did the cover art for the British releases of the soundtrack albums.
* RealSongThemeTune: The theme for the radio show was a snatch of the Music/{{Eagles}}' "Journey Of The Sorceror", an instrumental from their 1975 album ''One Of These Nights''. It would be re-orchestrated for the TV series.

!![[Series/TheHitchhikersGuideToTheGalaxy TV Show]] trivia:
* HeyItsThatGuy: The [[Series/DoctorWho Fifth]] [[Creator/PeterDavison Doctor]] as a creature that wants you to eat it!
*** Who at the time was married to [[http://tvtropes.org/pmwiki/pmwiki.php/Characters/TheHitchhikersGuideToTheGalaxy Sandra Dickinson.]]
** And the Black Guardian was the voice of Deep Thought.
** [[WesternAnimation/CountDuckula Igor]] was Garkbit the Waiter, or [[SherlockHolmes Inspector Lestrade]].
** [[Franchise/StarWars Darth Vader]] is Hotblack Desiato's bodyguard, and is responsible for his body. (David Prowse wore the Vader suit in Star Wars, but didn't do the voice.)
** [[Film/AClockworkOrange P.R. Deltoid]] is the captain of the Golgafrincham B Ark.
* PropRecycling: The background characters in the restaurant at the end of the universe are equipped almost entirely with costumes recycled from earlier episodes, and in particular from the various Guide entries, thus helping justify the expense of items which otherwise would have appeared on screen for only a few seconds each.
** A badge from one of the Golgafrincham hats would be worn by [[RedDwarf Arnold Rimmer]].