Fictional currency is currency in works of fiction. It is often invented, bearing little or no resemblance to any modern or historic currency. This is a necessary plot device, in order to increment the completeness of the environment, and at the same time dissociate it from any known economy on earth. A very common type, especially in science fiction, is credits. This is easily recognizable as money, and different from all earthly currency. The use of credits may serve to prevent the reader from inferring a lot of significance to it, e.g. by maintaining lack of depth that may be inherent to a short story, or simply to prevent it from overshadowing more important themes. However, this term would be inappropriate for a work set in a more technologically primitive environment, such as a medievalfantasy novel. Generic money in this genre is typically constructed from one or more precious or semiprecious metals, such as copper, silver, gold, electrum, or even platinum, followed by coins or pieces.
Doctor Who (sometimes specified as Galactic credits). In one serial the currency symbol is a Ƶ. A conversion ratio is mentioned in the episode "Voyage of the Damned": 1,000,000 pounds is equal to that of 50,000,056 credits.
Perimeter 2. The US dollar in the video game Perimeter 2 is denoted with the symbol similar to the American dollar sign ($), however, in the game, it is worth approximately as much as a Vietnamese dong, 6 x 10^-5 US dollars.
F-Zero video games and anime. A space credit, written with a symbol identical to a dollar sign ($), seems to be approximately equal to one Japanese yen, or about 0.8¢ US.
The Traveller role-playing game universe: CrImps, i.e. Credits Imperial, or "Imperial Credits".
The Galactic civilizations depicted in many Andre Norton books.
The space-faring 1964alternate history timeline of Fredric Brown's "What Mad Universe", abbreviated to "Cr.", with one Credit (a worldwide currency) having the purchasing power of about 10 American cents in our timeline.
The interstellar civiliazrion of A. Bertram Chandler's books uses both Credits (2000-2500 Credits pay for a ticket on a spaceship across many light-years' distance), and Dollars (lucky spacemen and spacewomen who did a major salvage job can get several million Dollars, which are enough to buy second-hand a spacship of their own).
In the TV series Firefly and it's follow on movie Serenity, credits are used by the more 'civilised' inner planets, while the out worlds use Platinum coinage.
Names adapted from real-world currencies
Air Dollars, used by the international association of pilots and technicians from which a world state develops in H.G. Wells' "The Shape of Things to Come" (1934). "The air-dollar was not a metallic coin at all; it was a series of paper notes, which represented distance, weight, bulk, and speed. Each note was good for so many kilograms in so much space, for so many kilometres at such a pace. The value of an air-dollar had settled down roughly to a cubic metre weighing ten kilograms and travelling two hundred kilometres at a hundred kilometres an hour" (see [1]).
Nuyen in the Shadowrun roleplaying game, based on the above.
Piastras were used in many of the comics of Spanish Editorial Bruguera during the Franco era. Using an undetermined foreign currency instead of pesetas allowed more leeway against the censorship.
Sens in Fullmetal Alchemist (technically not fictional, the sen being a former subdivision of the yen)
Sequins are the Martian unit of currency in Kim Stanley Robinson's Red/Green/Blue Mars series, as well as on Tschai (Planet of Aventure) by Jack Vance, where they are made from the roots of a plant that concentrates certain minerals.
The actually-existing Swiss Franc has a great fictional future in the loosely-linked stories included in Jerry Pournelle's "High Justice" (1974). The Swiss curency becomes a world-wide, and afterwards a Solar System-wide, medium of exchange (especially in the Asteroid Belt, where much of the action takes place).
Days from the Terry Pratchett novel Strata. One day is the amount of money that will buy you the rejuvenation treatment needed to increase your lifespan by one day.
Flanian pobble bead from The Hitchhiker's Guide to the Galaxy. Not an especially useful currency, as they can only be exchanged for other Flanian pobble beads.
Fretzers from Dr Trifulgas: A Fantastic Tale by Jules Verne.
Marinera, a currency used in Malynera Kingdom from Patalliro! (ja:パタリロ!). Consisted of five subunits, namely Nemarira, Rarinema, Marinera, Maraneri, and Manerari. Preceding units are 100 times more valuable than succeeding units, meaning 1 Nemarira is equal to 100,000,000 Manerari.
Monies from Invader Zim (on Planet Irk, Irken Empire).
Nargs in the Doctor Who serial "The Two Doctors", including a 20-narg note, which "can be changed in any of the nine planets".
Ningi, a triangular rubber coin six thousand eight hundred miles along each side, from The Hitchhiker's Guide to the Galaxy. It is valued at the rate of eight Ningis to one Triganic Pu, but thanks to the Ningi's immense size (almost twice as wide as the Earth's equatorial radius), it is more-or-less impossible to collect enough to own one pu. The inspiration for this may have been the Rai stones of the island of Yap.
Zenith, divided into Minims, the currency in the universe of Walter Jon Williams' "Dread Empire's Fall" series. A single Zenith has a considerable purchasing power, comparable to a 19th Century British Pound. Five Zeniths are enough to settle a moderate debt incurred in a card game, a hundred Zeniths are half a year's earnings of an ordinary person, a skilled artist giving personalised service to an aristocrat earns 15 to 20 Zeniths a month, gangsters showing off their money can spend hundreds of Zeniths in a single evening, the freedom of a detainee can be procured from corrupt police for 35 to 200 Zeniths (depending of the prisoner's importance), 3000 Zeniths is a tempting reward for a the head of a wanted criminal or rebel, a small estate could be bought for 9,000 Zeniths, the entire property of a minor noblewoman amounts to about 30,000 Zeniths, 14,000 Zeniths is a bargain price for a ju yao porcelain pot of the Song Dynasty, 80,000 is the price of a surviving Rembrandt painting, 200,000 Zeniths can assure a person of a comfortable lifetime livelihood (though the truly rich big aristocrats have much more). There is no paper money, the Zenith is either a metallic coin even in the high denominations or virtual electronic money in banks.
Exchange media
These are not currency as such, but rather nonstandard media of exchange used in certain works of fiction.
Dirt from Waterworld (Since the world was covered in water, dirt was a valuable thing).
Latinum, or Gold-Pressed Latinum, used by Ferengi in the Star Trek universe, is a fictional liquid, stored in gold slips, strips, bars and bricks in standardized amounts. Latinum derives its value from being non-replicable by any known existing or predicted replication technology.[1] It should be noted that, as Quark points out in "Who Mourns for Morn?", the gold in Gold-Pressed Latinum is merely a convenient material in which to suspend standardized quantities of Latinum, which, as Rom points out in reply, is somewhat awkward to use as cash due to being a liquid at room temperature and standard pressure. (Compare with events in Venus Equilateral: in one episode, the crew of the titular space station invent similar replication technology, inadvertently creating a solar-system-wide inflation crisis (suddenly anyone can materialize all the cash they want out of thin air at the push of a button), which they then solve in the next episode by developing a substance which cannot be produced by replicators to be used to create non-replicable currency.)
Masses of the high-energy rare mineral Naqahdah in several grades is used as a galactic currency of sorts in Stargate SG-1. The value of the Prometheus appears to have been a suitcase-sized chest of weapons-grade naqahdah, the most refined kind of naqahdah.
Credits are used in a number of games (mostly Sci-Fi and Space Adventure games). The name may also vary in spelling and region ("Inter Stellar Kredits / ISK" in EVE Online, for example).
Nuyen, in the ShadowrunRPG is the 21st-century corporate standard of international exchange. An homage to the works of William Gibson (see 'New Yen', above).
Rings, from the Sonic the Hedgehog video game series. These did not have actual monetary value until Sonic Advance, where they could be used to buy items for the player's Chao.
Tokkul,an obsidian coin used in RuneScape by the Tzhaar
Trading Sticks are the curreny of Karamja in RuneScape
Tiberium, though not an actual form of currency, is a disruptive resource that is converted into Credits (the game's actual currency) in the video gameCommand & Conquer.