The Hitchhiker's Guide to the Galaxy Douglas Adams

Future predictions

While Adams' writing in The Hitchhiker's Guide was mostly to poke fun at scientific advance, such as through the artificial personalities built into the work's robots, Adams had predicted some concepts that have since come to be reality. The Guide itself, described as a small book-sized object that held a great volume of information, predated computer laptops and is comparable to tablet computers. The idea of being able to instantaneously translate between any language, a function provided by the Babel Fish, has since become possible with several software products that work in near real-time.[86] In the Hitchhiker's Guide to the Galaxy, Adams also mentions computers being controlled by voice, touch and gesture, a reality for humans today.

"Hitch-Hikeriana"

Many merchandising and spin-off items (or "Hitch-Hikeriana") were produced in the early 1980s, including towels in different colours, all bearing the Guide entry for towels. Later runs of towels include those made for promotions by Pan Books, Touchstone Pictures / Disney for the 2005 movie, and different towels made for ZZ9 Plural Z Alpha, the official Hitchhiker's Appreciation society.[88] Other items that first appeared in the mid-1980s were T-shirts, including those made for Infocom (such as one bearing the legend "I got the Babel Fish" for successfully completing one of that game's most difficult puzzles), and a Disaster Area tour T-shirt. Other official items have included "Beeblebears" (teddy bears with an extra head and arm, named after Hitchhiker's character Zaphod Beeblebrox, sold by the official Appreciation Society), an assortment of pin-on buttons and a number of novelty singles. Many of the above items are displayed throughout the 2004 "25th Anniversary Illustrated Edition" of the novel, which used items from the personal collections of fans of the series.

Stephen Moore recorded two novelty singles in character as Marvin, the Paranoid Android: "Marvin"/"Metal Man" and "Reasons To Be Miserable"/"Marvin I Love You". The last song has appeared on a Dr. Demento compilation. Another single featured the re-recorded "Journey of the Sorcerer" (arranged by Tim Souster) backed with "Reg Nullify In Concert" by Reg Nullify, and "Only the End of the World Again" by Disaster Area (including Douglas Adams on bass guitar) listenⓘ. These discs have since become collector's items.

The 2005 movie also added quite a few collectibles, mostly through the National Entertainment Collectibles Association. These included three prop replicas of objects seen on the Vogon ship and homeworld (a mug, a pen and a stapler), sets of "action figures" with a height of either 3 or 6 inches (76 or 150 mm), a gun—based on a prop used by Marvin, the Paranoid Android, that shoots foam darts—a crystal cube, shot glasses, a ten-inch (254 mm) high version of Marvin with eyes that light up green, and "yarn doll" versions of Arthur Dent, Ford Prefect, Trillian, Marvin and Zaphod Beeblebrox. Also, various audio tracks were released to coincide with the movie, notably re-recordings of "Marvin" and "Reasons To Be Miserable", sung by Stephen Fry, along with some of the "Guide Entries", newly written material read in-character by Fry.

Towel Day

Celebrated on 25 May, Towel Day is a fan-created event in which they carry a towel with them throughout the day, in reference to the importance of towels as a tool of a galactic hitchhiker described in the work. The annual event was started in 2001 two weeks after Adams' death.[89]

42, or The Answer to the Ultimate Question of Life, The Universe, and Everything

In the works, the number 42 is given as The Answer to the Ultimate Question of Life, The Universe, and Everything by the computer Deep Thought. The absurdly simple answer to a complex philosophical question became a frequent reference in popular culture in homage to The Hitchhiker's Guide, particularly within works of science fiction and in video games, such as in Doctor Who, Lost, Star Trek and The X-Files.[90][91]

2020 was the 42nd anniversary of HG2G appearing on Radio 4. The book Hitchhiking: Cultural Inroads was dedicated to the memory of British actor Stephen V. Moore who died in Oct 2019 and played the voice of Marvin the Paranoid Android in the original BBC Radio and Television Series.[92]

Other references in popular culture

Two asteroids, 18610 Arthurdent[93] and 25924 Douglasadams[94] were named after Arthur Dent and Douglas Adams, as both had been discovered shortly after Adams' death in 2001. The fish species Bidenichthys beeblebroxi and moth species Erechthias beeblebroxi were both named after the character of Zaphod Beeblebrox.[91]

Radiohead's song "Paranoid Android" was named after the character of Marvin the Paranoid Android. The band's singer Thom Yorke used the character's name jokingly, as the song was not about depression, but Yorke knew many of his fans felt that he should seem to be depressed.[95] The album OK Computer which "Paranoid Android" appears on is also taken from The Hitchhiker's Guide, referencing how Zaphod would address the Heart of Gold's onboard computer Eddie, and was selected by the band after listening to the radio plays while travelling on tour.[96]

SpaceX CEO Elon Musk has stated that The Hitchhiker's Guide is one of his favourite works, his "favorite philosopher is Douglas Adams" and his favourite spaceship ever is in The Hitchhiker's Guide.[97] Musk said the attitude that Adams presented through The Hitchhiker's Guide had influenced the vision behind both SpaceX and Tesla Motors.[98] When Musk launched his Tesla Roadster into an elliptical heliocentric orbit as part of the initial test launch of the Falcon Heavy, he had a copy of Douglas Adams' novel The Hitchhiker's Guide to the Galaxy in the glovebox, along with references to the book in the form of a towel and a sign on the dashboard that reads "DON'T PANIC!", as a nod to the Hitchhiker's Guide.[99]