Global Currency

"Sagat: This money isn't worth the paper it's printed on!

Bison: On the contrary, every Bison dollar will be worth 5 British pounds. For that is the exchange rate the Bank of England will set once I've kidnapped their queen."

- The Street Fighter movie.

A single form of currency is accepted universally worldwide, regardless of political, social, or technological differences. No matter whether you're dealing with cavemen who speak in broken English or beings from another planet, your money is always good at face value. An almost ubiquitous trope in RPGs and in most other games involving some kind of economy.

The currency in question often has a generic name that implies no place of origin (often just "gold" in fantasy and almost always "credits" in science fiction) and as far as is observable by the player, is spontaneously generated in indefinite quantities within the game world rather than being minted or printed by a bank or government. Despite the fluid nature of this currency, it is seemingly immune to basic economic forces like inflation, supply and demand, devaluation, and Gresham's Law.

The primary Global Currency Exception is when the designers will insert a region where it isn't accepted in an to add difficulty to the later parts of the game.

This is an Acceptable Break From Reality-- imagine how taxing it would be to spend time in video games changing from currency to currency. It can be justified by an Energy Economy, or coins minted out of valuable metal.

Anime and Manga

 * Anime example: Woolongs in Cowboy Bebop, accepted throughout the Solar System.
 * Likewise Wongs, accepted throughout the galaxy in Outlaw Star.
 * Berries in One Piece.
 * Justified, since their world is dominated by the World Government, which controls nearly every country on the planet to various extents.
 * Averted in the Skypeia saga, which takes place on an island in the sky which the World Government is not aware of. Instead they use a currency called "Extol." 1 Beri is worth 10,000 Extol.
 * Rin in Letter Bee.
 * In Robotech the movie not only was their a Global Dollar but a news reporter talks about it being devalued... devalued against what?
 * Inflation, probably?
 * Double-Dollars in Trigun

Fan Works

 * In With Strings Attached, the Baravadans don't care that the four are using Ketafan money. That's because the continent is an anarchy, and the inhabitants seem to use money more out of habit than necessity.
 * On the other hand, the Hunter's world is more normal, and the big man expects to have to melt down the money he brought with him to C'hou, lest he be arrested. The four set him straight.
 * Although the issue is not explicitly raised when the four have to use their C'hovite currency in the shop at the Inn at the Gate, the Hunter notes that the shop caters to "unprepared, and shall we say, hurried travelers," so presumably they're used to unfamiliar coinage.

Film

 * Apparently, this happening in the real world is supposedly a sign of the coming Antichrist... or maybe that's just how it played in the Left Behind movies.
 * I don't think it's ever explcitly stated, but the book of Revelation makes references to people who don't bear the mark of the antichrist as being unable to trade. The movies and novels of the Left Behind series bumped this up to having global currency, meaning it would become much easier to stop unmarked traders.
 * In the books, at least, the Nick is introduced as the standard global currency before it gets replaced by the cashless "mark of loyalty" system, which is the Mark of the Beast. Nothing is mentioned in Kingdom Come what the Millennial Reign residents use for currency.
 * In the animated film Starchaser: The Legend of Orin, currency is referred to as "starbacks".
 * Rather hilariously averted in Star Wars: The Phantom Menace ("Republic credits? Republic credits are no good out here"--because no one on a backwater planet--which nonetheless has spaceports, is crawling with interstellar smugglers, etc.--would accept the currency of the galactic superpower, not even at, say, some really cut-throat exchange rate.)
 * It's a Hutt planet. As in part of the Hutt Empire, an entirely different culture and economy. The currency Watto is asking for is essentially Hutt credits. Later on, the Emperor manages to make the Imperial credit strong enough that even unaffiliated planets use it.
 * That still doesn't take out the Fridge Logic of a planet full of starship captains, smugglers, and traders absolutely refusing to take Republic currency when just about anyone in the city is there on temporary business before heading off to space where they are guaranteed to pass through Republic territory. Plus, the Hutts have dealings with the Republic, so the idea that there is no one on all of Tatooine who would take, or at the very least, exchange Republic credits is ludicrous.
 * According to the EU there were a few vendors who would take the Republic credits as well as moneychangers, but the rates were bad. Additionally, going to a changer could have revealed the Queen's presence. Going to another vendor wasn't an option for Qui-Gon because only Watto had the parts he needed. Though another question arises. Was "Republic Credits are no good here" true for everybody?
 * Possibly Watto just didn't want to deal in currency because he wanted to keep his dealings with a couple of Jedi as off-the-books as possible. He did live on a planet run by gangsters, after all: cutting deals with the Galaxy's cops may not have been all that safe for him.
 * Watto didn't even know they were Jedi, though he almost figured it out ("What, you think you're some kind of kind of Jedi or something, waving your hands around like that?"). Maybe he just trades too many illegal goods to be able to deal in big-name currency?
 * 1980's Galaxina had "Earth Yen".

Literature

 * In David Wingrove's Chung Kuo series, the Chinese yuan is now the global currency.
 * Likewise, the Imperial credit found in Isaac Asimov's Foundation trilogy, which was usable throughout the Galactic Empire, and Foundation dollars later in the series.
 * Discworld has many currencies, but outside the Agatean Empire, the Ankh-Morpork dollar is accepted everywhere "because Ankh-Morpork is the only place with anything worth buying". Areas like Lancre and the Chalk don't seem to bother having their own currency; if you're buying something from outside the area you use AM$, and within the area you barter.
 * Played with in Star Wars books: There are Republic credits and Imperial Credits. At one point in The Thrawn Trilogy Luke needs to help two arguing person to settle their dispute and ask the exchange rate between two factions.
 * Partially subverted in The Wheel of Time series. All of the Westlands has the same name for the different coins (crowns, marks, and pennies) but coins from different countries weigh different amounts or are of different purities. The Andoran golden crown is the most valuable since it weighs the most. Crowns are made from gold or silver, marks from usually silver but occasionally gold, and pennies are sometimes silver but usually copper. As such, merchants weigh almost all transactions to make sure they know how much the coins are worth.
 * In William Gibson's Sprawl Trilogy the globe works on a digital economy with various currencies, however a global black market physical currency exists in the form of New Yen. Apparently they are very illegal in Japan.
 * Last Legionary: Credits crop up as a Galactic standard currency in Douglas Hill's scifi series.

Live Action TV

 * Averted on Stargate SG 1: There is no universally accepted currency. In fact very rarely is any currency mentioned at all and never for interplanetary trade. Though people often barter with naquadah.
 * Also averted in Stargate Atlantis: Not only is there no universally-accepted currency, trade in the Pegasus Galaxy appears to operate primarily on the barter system.
 * Averted in Babylon 5: While the usual currency on B5 is "Credits," the existence of Centauri ducats (apparently gold coins with a very high exchange rate to Credits) appears to imply that the "Credit" is merely the human currency, and other races have their own forms of money.
 * In fact the Centauri ducats seems to be closer to a universally accepted currency, if only because the Centauri Republic is a long established economic power. Additionally, it seems that since ducats are hard, physical currency, they are much preferred to the electronic human credits for shady deals and the informal economy (of which, given that Babylon 5 is a show about a living city-cum-United Nations in space, complete with seedy slums and underhanded politics and espionage, we see a great deal).
 * Similar to B5, The Federation in the Star Trek franchise use credits, but once you get to the outer reaches, everyone prefers gold pressed latinum, particularly the Ferengi. Of course it's the latinum that valuable, the gold is just a pretty container for it.
 * The latter part applies only after the invention of the Replicator (Gold can be replicated; Latinum can't, which is the entire reason it became the universal currency). The Ferengi in the Enterprise episode were excited when Archer said he had gold bars instead of latinum.
 * In the Sid And Marty Krofft series HR Pufnstuf, the people (or whatever...) of Living Island use "buttons" as currency.
 * The Sliders crew didn't seem to have much of a problem with spending cash for supplies across dimensions, except in the first episode, where their attempts to use normal money instead of that particular planet's red-tinted "commiebucks" almost get them killed.
 * Justified in that they were just moving to alternate versions of the same place, so more often then not dollars would work fine. However they have used silver (and presumably gold) if California isn't American.
 * The "dollarpound" (or "quidbuck", if you're in a hurry) from Red Dwarf, although early episodes used pounds.
 * Firefly primarily makes use of Alliance credits, though this is because the Alliance controls most of the human-inhabited space. There is also mention of people trading in platinum instead of credits, with Simon mentioning the different values of the medicine in his bag in terms of both credits and platinum. Dollars and cents are mentioned in the episode Jaynestown (In the Ballad of Jayne Cobb)

Mythology & Religion

 * In Revelation 13:16-17, as part of the tribulation facing mankind in the End Times, the Beast will force everyone to receive a mark on their right hands or on their foreheads, and no one will be able to conduct business without the mark. This "Mark of the Beast" has been subject to much speculation. One interpretation is that it's not a literal mark on the hand or forehead, but a symbol that has to appear in some manner in all monetary transactions. A worldwide single currency would fit the bill for such a symbol.

Tabletop RPG

 * In Mortasheen, the universal currency is actually blood, due to how useful it is for the typical mad-science-related going ons. They even have a monster created to hold and dispense it.
 * In Dungeons and Dragons, the base unit of currency everywhere is the gold piece (g.p.). Acquire gold pieces from a street vendor in Greyhawk, and you can spend those same coins in a shop half way around the world without anyone batting an eye. Some DMs attempt to justify this, and the Dungeon Master's Guide has recommendations for different monetary systems that may come up. As one might expect, most Dms just use gold pieces.
 * Although currencies are generally global (probably based on the intrinsic value of the material itself -- the weight of a gp varies by edition, typically 10 gp per pound in older editions and 50 gp per pound in newer), this isn't necessarily true from one world to the next. The world of Krynn in the "Dragonlance" setting uses steel pieces rather than gold. The change in the weight of the coin seems largely to address certain logistical challenges in hauling large sums out of dungeons.
 * The 4th Edition rulebook explains that those "GP", "SP", etc. were the coins used by the last great empire to fall, which makes them acceptable in most lands formerly ruled by it.
 * That explanation itself is a prime example of You Fail Economics Forever, as a fallen empire's currency would be worth practically nothing. Without a governing body to back the currency and give the people faith in it, the coins would fall to being worth only their material wealth. The only reason old coins today are worth anything is because of collectors, and none of them are accepted as currency.
 * In Classic Traveller, the Imperial credit was accepted throughout the interstellar Imperium, which was made up of thousands of planets in an area hundreds of light years across.
 * And a mild aversion: Physical money in the Imperium has the bank of issuance printed on it. If one sector's economy starts to collapse, the Imperium can simply declare money from that area invalid, thus firewalling the problem.
 * The Star Ace game featured a not-all-the-way-to-war between the Empire and the Alliance. (It's a game from the 80s, so just think original Star Wars.) Both use the same currency. Granted, this is a game setting where all money is solid metal coins, so as long as everyone agrees on how valuable the metal is ....
 * In Cyberpunk 2020 the most common worldwide currency (and the only one mentioned in the base materials) is eurodollar, commonly shortened to euro. Funny In Perspective.
 * Long before the advent of the euro, Real Life currency traders used the term "eurodollar" to mean U.S. dollars invested in Eurpoean banks.
 * There is a throwaway line in the CP 2020 core rulebook about 2 US dollars equaling 1 eurobuck (eb). Meanwhile, the Pacific Rim sourcebook implies yen and yuan are still minted but East Asia still recognizes eurobucks as the fiat currency.
 * In Shadowrun the currency universally accepted in North America and most countries in the world is nuyen (new yen).
 * Which, like a number of items in Shadowrun's setting, is a nod to William Gibson, specifically the Sprawl Trilogy.
 * Massively averted in Das Schwarze Auge inhabitants of Dere use few dozens types of coins and every country or state usually has its separate currency system. Some have more than one.
 * Also heavily averted in Warhammer Fantasy Roleplay. Empire uses, well... Imperial system comprising of golden crowns, silver shillings and copper pennies. Some cities have the right to mint its own coins. Other countries have their own currency, e.g. Estalian excellentes, reals and duros, Kislevian ducats and dengas etc. It is explicitly stated that money minted in less stable regions (e.g. Tilean city-states) is usually considered worthless abroad.
 * Played with Seventh Sea. The Vendel have introduced the Guilder, a universal currency. It is also the first paper currency, enabling people to carry more of it at once. All rule-supported prices are listed in Guilders. However, the Vesten and Vodacce, the Vendel's most bitter enemies, refuse to accept the Guilder in order to undermine the Vendel.

Video Games
"Iolo: I can understand the whole laundering your magically counterfeit coins, but why are we exchanging them for gold instead of guilders?
 * Gold coins in most fantasy games. Now, this is justified as long as the materials of the coins are intrinsically valuable to all sides concerned. Historically, coins have often been regarded as conveniently pre-measured amounts of gold or silver: such old units as shekel, mina and talent were measurements of weight at least as much as currency . An unknown coin might be accepted after a trip to the scales, without regard to what shape it's in or whose portrait is stamped on it. A well-trusted coin would simply assure the recipient that it wasn't made of cheap alloy.
 * Planescape Torment deserves special notice as using copper as the base of the economy... and doing so across multiple planes of existence.
 * Explained in the Planescape tabletop RPG books that copper, silver, and gold coins are... well, they're copper, silver, and gold. Money's flowing to and from everywhere, especially through Sigil, so that it's pointless to even try to care about the face stamped on the coinage. Thus, it's advised in the books that while it may be fun to hassle players once or twice about how the coins from their homeworld are "too small," and given a surcharge by greedy merchants, for the most part it should be taken as given that your money will be good anywhere.
 * The most common coinage in the Celestial Planes is a particular type of silver coin minted on Mount Celestia (oddly shaped, but still counts as a "normal" silver coin). The Lower Planes have an additional type of currency: souls. Trapped in black gems. Exchange rates are variable.
 * In Real Life, even when coins were treated this way, kingdoms in the habit of minting their own currency might have laws requiring people to change other kinds of currency in for their own. This had the advantages of keeping locally minted money in circulation, and of being very profitable for the moneychangers. Also, this did nothing to keep the prices of goods stable, so it solves none of the "immunity to economic forces" issues. During the days of the gold standard real wages were actually wildly more variable than today because national currency was constantly being artificially revalued to match the global standard.
 * They also tended to inflate their currency by replacing part of the weight with something else.
 * Gil or GP (depending on the translation) in the Final Fantasy games and many other games by Square Enix and its predecessors.
 * Exception: Final Fantasy VII uses gil everywhere but in Gold Saucer, which uses GP (won on the various rides, or bought from shady dealers).
 * Exception: Final Fantasy XI uses gil in most parts of Vanadiel except for some parts of the eastern empire of Aht Urghan. Many transactions that need to be made here can only be done with imperial currency and not gil.
 * It's done again in Wings of The Goddess, where most transactions in the Crystal War are done with Allied Notes, which are pretty much war bonds.
 * It should be noted that Gil started as Jeuno's currency, and only became the standard currency in Quon and Mindartia (the continents the game mainly takes place, aside from Aht Urghan) 20 years or so prior during the Crystal War. Bastok, San d'Oria, and Windurst had their own currency, Byne, Noit, and Mumu respectively.
 * Rupees in The Legend of Zelda series, although in that game you're usually only in one country for the duration of the game, so it's not as noticeable. Still, the games that do take place in different countries still use rupees for currency.
 * An exception is in Oracle of Seasons, which features an underground area called Subrosia. Rupees are useless there. The only currency usable there is Ore Chunks.
 * Not Oracle of Ages, however, in which Labrynna continues to use the same currency with no alterations whatsoever over a period of a few hundred years.
 * Also of note is The Legend Of Zelda Four Sword Adventures, where Force Gems are used instead.
 * "Credits" in Star Wars games and many other science fiction games.
 * Imperial Credits are used EVERYWHERE in Star Wars: Empire at War. Even planets without populations and no obvious source of income (Endor, Yavin IV, Hoth, etc.) pay to the player the same type of Credits.
 * Mesetas in the Phantasy Star series.
 * Zenny in numerous Capcom games, most notably Breath of Fire. (Of course, "zeni" is just a slightly archaic Japanese word for "money".)
 * Gets odd in the Megaman Legends series; despite being tens of thousands of years into the future from any other Capcom games, the currency is still Zenny.
 * Plus, back when the word was still in use, it probably didn't mean gemstones the size of your head.
 * Battle Network also uses zenny as the name of its currency.
 * Ragnarok Online also uses Zenny. Even odder here as as the player is able to visit at least two different neighboring nations.
 * Justified in Fallout, the water merchants (who control the most valuable commodity in the game's post apocalyptic world) back the use of bottle caps used as currency.
 * In the sequel, New California Republic dollars (represented with some sort of coin or chip) are used instead. One particularly stereotypical Fetch Quest ends with you obtaining a bag of ten thousand bottle caps... which are, of course, utterly worthless. Some players love to collect unique items and include the bag on the list.
 * Fallout 3 then goes back to caps, despite the fact that the first two games take place in the California area (where the currency is backed by the water merchants) and the third game is in Washington DC (where the currency is apparently backed by no one, although it's possible that the Canterbury Commons trade consortium endorses it). It gets inexplicable when you meet characters that will accept caps even though they likely never interact with any other cities. Fiat currency is worthless to hermits. One can occasionally find stacks of "pre-war money" in ruins, which can be sold for a handful of caps.
 * Oh, Fallout Tactics gets even better. The Brotherhood in Chicago and the Midwest apparently uses Brotherhood scrip--but only internally. The currency of choice in the Wastes? Ring pulls.
 * Fallout New Vegas uses caps as well, this time backed by the Crimson Caravan Company. NCR dollars, Legion denarii, and pre-war US dollars can also be found and spent throughout the game, though caps are the "default" currency. According to the backstory, the Brotherhood of Steel destroyed the NCR's gold reserves, severely devaluing the NCR dollar and forcing a shift back to caps thanks to the water merchants.
 * Averted in the Dead Money add-on, though. The expansion takes place in a casino that sealed just before the war that destroyed the Fallout universe. As a result, no vendors carry caps, and so finagling with Pre-War money and Vendor Trash is required. The Casino's chips are used as an alternate currency in vending machines.
 * Septims in The Elder Scrolls series, though this is more logical than most examples of the tropes; the Cyrodiilic Empire actually governs the entire game world, and mints the coins itself.
 * This trope was also lampshaded in Elder Scrolls III: Morrowind. The nomadic barbarians known as Ashlanders considered the player character to be a fool for trading them useful items in exchange for small chunks of metal with no practical use. Of course, they still ask for them too.
 * In books and conversations ingame, more than one name ("drakes", "septims") is used to refer to money, implying that Tamriel operates on something like a gold standard.
 * This is because the Imperial coinage has names based on the design of it's head and tail. On one side is the head of Tiber Septim, on the other is a dragon. Thus, Drake refers to the tail side, Septim refers to the head side.
 * Averted in Square's Secret of Evermore, in which the four "lands" that make up the game each have their own distinct unit of currency and will not accept money from other lands. However, the exchange rate of the currencies remains fixed throughout the game.
 * Also averted in the MMORPG RF (Rising Force) Online where each faction has their own currencies, with fluctuating exchange rate.
 * Subverted in Shin Megami Tensei. During the first half of the game, which takes place in Tokyo, you use Yen. But when a cataclysmic event throws you into an After the End future, you discover that in this Scavenger World, your Yen are as worthless as the paper they're printed on.
 * Later referenced and subverted again in Shin Megami Tensei Nocturne. For one Fetch Quest you're asked to retrieve a 1000 Yen Bill: the smallest amount of paper currency in Japan, but After the End an incredibly rare, valuable collector's item.
 * The replacement currency, Makka, is not only legal tender on Earth, but in the Abyss as well (in SMT 2). It is also minted exclusively by Lucifuge Refocale, one of Lucifer's minions. Money might not be the root of all evil, but...
 * Evil is the root of all money?
 * In Saga Frontier, "credits" are used as a universal currency, but you are also able to buy gold bars. There is a famous glitch that lets you make obscene amounts of money through manipulation of the gold market, dubbed "Takeonomics" after its discoverer.
 * Princess Tomato in The Salad Kingdom ignores this trope by giving the player gold at several turns... but making the gold almost useless. On the few occasions you do need money, the gold needs to be traded in for proper currency.
 * Avoided in Ultima VII Part II: Serpent Isle, where in addition to gold coins, each of the three cities featured in the game have their own currency. While some merchants accept payment in more than one currency, none accept all, and some characters exchange the various currencies at variable rates.
 * And then Steve and pals came to Moonshade with False Coin and an extensive knowledge of the game's mechanics...

Steve the Avatar: Iolo, after all the money we just dumped into the economy, the Guilder is about to go to shit."

"Steve: The good thing about money in this kingdom is it's all unmarked and unsecured. Nobody cares if I took it from somebody, or got it from an extradimensional entity, or transmuted it from lead, doesn't matter. How does this kingdom even function?""
 * That's not the first time the Avatar wrecked the economy, either. In Ultima 6 you can dump a ridculous amount of gold into the economy, which you received from an extradimensional entity with very limited understanding of monetary value. (You share the contents of a useless book of mantras, Xorinia gives you all the gold your party can carry, literally. Xorinia is firmly convinced you made the losing deal.)
 * In the Ultima VII LP, Steve herself lampshades the vulnerabilities of the Britannian economy:


 * "Munny" in the Kingdom Hearts series's multiverse-spanning economy. Its name appears to be a reference to Winnie the Pooh, in which Pooh consistently spells honey as "hunny" on his various jars and pots.
 * Sierra's Space Quest series had "Buckazoids", a currency that was accepted not only everywhere in the universe, but everywhere in time when one of the games sent the hero time traveling.
 * In MOTHER 3/Earthbound 2, there is no currency for half of the game, and trade relies on bartering for items with things like rotten éclairs. After the midway point, money is introduced into the world. This may also be commentary about the evils of money, since this currency is introduced by the antagonists, and it is at this time when the game's world begins to get screwed up.
 * Earthbound uses dollars for every single place you go. This seems silly to use a dollar in a foreign country on a mountaintop, a village in a swamp, or even in a tiny village in an underworld full of dinosaurs!
 * There's only one shop in the game where dollars aren't used, and that's in Tenda Village. The shopkeeper trades items for Horns of Life.
 * At least the Mountaintop country's store specifically advertises accepting $ Dollars. It's good business to cater to those tourists, you know!
 * Bolts in Ratchet and Clank. Even when Ratchet goes over to another galaxy, they still use Bolts as currency.
 * Civilization universally uses "Gold." Semi-subverted in that techs, units, etc., get more expensive as time goes on (i.e. inflation), and indeed "inflation" is a game mechanic in Civilization IV to keep your economy from getting too big.
 * Of course, a quick look at history shows that gold-standard economies experience very little inflation and prices in industrialized economies drop very rapidly without it.
 * After construction the New League of Nations, its Secretary-General can put up a vote for global currency, which increases commerce for all.
 * Sid Meiers Alpha Centauri mentions the difficulty of founding a new economic system while settling a new planet. The world uses energy as a global currency, measured in energy credits. This works in much the same way as gold in Civilization, but one does get richer by settling high elevations and constructing solar collectors.
 * Kingdom of Loathing uses meat. The creators say this was because they didn't have a picture of a pile of coins, but did have a picture of a piece of meat. It also works as a good Lampshade Hanging, as it makes more sense to be able to pull a fistful of meat off the corpse of a dead mammal than a fistful of dollars. However, outside the Seaside Town there are almost as many places that use their own local currency as there are places that use meat.
 * Somewhat averted in Sierra's Quest for Glory series. The local currency for each game needed to be exchanged at the moneychanger when you went to a new country in the next game. However, the exchange rate is usually one-to-one (minus the moneychanger's service charge).
 * Bells in Animal Crossing. Subverted by one of the messages the player may receive when searching a dresser in a neighbor's house: "You found 100 Rupees! But you can't use them here."
 * Lampshaded in Chrono Trigger. When the party travels to the distant future or the remote past, merchants don't recognize their money (Although they end up taking it anyway. Gold's gold, no matter what funny pictures get printed on it). Oddly no one in the present has a similar reaction when the party spends money acquired in the year 2300 AD or 65 million BC.
 * The money is accepted in the future because, well, they don't exactly have anything else, really. The money is also accepted in the past because, as the trader says, he wants your "shiny stone", and is willing to give you stuff for it.
 * Also contains a partial subversion: The "weapons shop" in prehistoric era refuses to take money, and will only accept trade goods from their hunting grounds (horns and the like). There is another caveman nearby, however, who's more than happy to "trade your shiny stone" for healing potions. And before you ask, the weapons you can acquire there (then, rather) are superior to the far future ones you have currently...
 * Mario & Luigi Superstar Saga subverts this in two places: Mario is given 100 coins before leaving for the Beanbean Kingdom. It turns out upon attempting to placate a local Beanbean creature's demands that the original 100 coins plus whatever he had heretofore earned was only worth 10 Beanbean coins.
 * Later, Prince Peasley makes a bet that he will get the pieces of the Beanstar first... a bet of 99,999,999 Mushroom Kingdom coins. Upon receipt, it comes to light that Mushroom Kingdom coin value against Beanbean coin value has fallen sharply, totaling only 99 Beanbean coins.
 * It would make sense that the Mushroom Kingdom's currency isn't exactly... stable. Their princess has been kidnapped around... 12 times before the game starts.
 * Also subverted in Super Paper Mario when Mario has to work off a debt of Rubees.
 * The second and third Donkey Kong Country games involve using two types of coins: "regular" coins for getting important items (banana coins and bear coins respectively), and "special" coins for unlocking hidden levels (Kremkoins and "Bonus coins"). Actually, both games also have a third type: a giant one with "DK" on it, but those are just for getting One Hundred Percent Completion.
 * Subverted in Mass Effect at first "credits" appear to play this trope straight. However, the codex states, credits have a floating exchange rate that is calculated in real-time with the currencies of local planets and countries, meaning that anyone on Earth can convert credits to their value in, say, dollars or yen with a press of a button.
 * It's mentioned that there wasn't a single "credit" system in the galaxy until the Volus entered the galactic scene. Interestingly, credits also work outside of Citadel space.
 * The main currency on Anachronox, the money that is accepted all over the universe, by all the established races in the game, is... the Canadian dollar.
 * Specifically, the loonie dollar coin. Paper is not accepted.
 * Averted hard in the Dwarf Fortress. Currency of civilizations can only be traded for the worth of their base metals outside of the one they're minted in, making them virtually worthless.
 * In the MMO EvE Online, the standard unit of currency accepted everywhere (including between factions that are at Cold War with each other), is the Interstellar Standard Kredit, or ISK. Being that a large economic simulation is a key part of the game, literal financial empires are built on this standard.
 * ISK is the universal currency used by capsulers, but there are countless other currencies used by people planetside. The ISK is just used to facilitate trade between people bouncing around the galaxy with budgets the size of planetary GD Ps.
 * The name is something of a Bilingual Bonus too -- the game's developers, CCP, are based out of Iceland, which uses ISK as the standard code for the Icelandic currency, the króna.
 * Wonder if the in game currency will change to the euro soon...
 * In Shadow Hearts 2, despite the game taking place in various countries around Europe and Japan during WWI, the same currency (called, simply enough, "money") is accepted everywhere.
 * Fol in the Star Ocean series is, in fact, intergalactic currency. Whether you're in a primitive planet based on 12th century or in a super-advanced planet, you use Fol to pay for your items.
 * The Space Stage in Spore is a particularly Egregious example: every space-faring civilization in the galaxy uses the same unit of currency. Which wouldn't be too bad, except that this includes your civilization before you've made contact with anyone else.
 * The Shadowrun RPG features Nuyen, which, as the name implies, is a new form of the yen. It's accepted everywhere.
 * The use of "credits" in the Crusader games is perfectly justified by a global corporate hegemony. However, it's implied to be at least partially electronic-based money, which means it would be an odd choice for taking to the black marketeer you use to buy your toys at, no?
 * While mostly done straight in the MMO World of Warcraft, with the currency consisting of copper, silver, and gold pieces across all factions, the game has dozens of currencies--eleven from Pv P alone (Honor points, arena points, six different marks of honor, marks of Honor Hold/Thrallmar, and the Halaa tokens) and five obtained from bosses, usually exchanged for epic gear. There are also minor factions that only accept a particular currency for their goods: Sporeggar only takes a certain mushroom; Ogri'la only takes a certain crystal; the Winterfin murlocs only take a certain species of clam, and then the inexplicable Venture Coins.
 * Fridge Logic hits when you realize that while all these specialist vendors only accept particular currencies for the stuff they sell, every single Sargeras-cursed one of them will buy anything from players, and pay for the items in standard Azerothian currencies.
 * The Warcraft and World of Warcraft tabletop roleplaying games actually averted this to a degree. While GP and copper, silver, and gold was the gameplay mechanic standard, the fluff made a point that the Horde hadn't started minting its own coins yet(it takes place before the MMO) and if trading in Horde territory, you were more likely to be doing business with gold nuggets and dust than coins.
 * Gaia Online has multiple currencies. The most common is Gaia Gold (g), which is used in most stores, and on the marketplace. The other official currency is Gaia Cash (gc, or GCash), which is obtained through microtransactions. GCash can be used in all shops except one, and certain items can only be purchased with cash. In addition, La Victoire (Cash Shop) and Phin Phang (Aquarium Shop) only accept G Cash, and the zOMG! Power Up items from Back Alley Bargains can only be purchased for cash as well. The Casino games use two forms of currency: Tokens and Tickets. These function identically to their real life counterparts (Tokens are used to play the games, and tickets are used to purchase prizes from Prize and Joy). Null Fragments are used by Nicolae for Item Crafting, and can be earned from quests or purchased for 25gc a piece. Finally, the Mythrill and Fail Coins are prizes from random boxes that can be sold for up to 5 Million Gold.
 * Aversion: In the Exile and Avernum series, the instructions say that the "gold" referred to in the game is not actual gold pieces, but random valuables (such as coins, small gems and animal skins) that can be used for barter underground. Quantifying it, therefore, seems to be a sort of translation for the benefit of us players, who are used to living in a society with quantified currency. (Although in the third game in the series, the party's finances are identical in Exile and on the surface?one would think that the Empire would have, if not a universal currency everywhere on the surface, at least some kind of currency.)
 * Justified in that although the Empire mints currency, adventurers are common enough that shopkeepers (especially those that deal with them regularly) would be used to dealing with them paying with the bartered spoils of their adventures.
 * Rings in Sonic Chronicles. Even once you're inside.
 * City of Heroes uses Influence (for Heroes and Vigilantes), Infamy (For Villains and Rogues) and Information (for Praetorians). While Influence and Infamy were originally separate currencies, Issue 18 consolidated the currencies into a single metaunit (INF), to facilitate trading between heroes and villains. The currency is designed so that a character uses her reputation and knowledge to get the equipment they need. ...However, as you can trade INF like a regular currency, this raises some odd questions. Most characters treat INF as an actual US Tender, rather than the metaphorical currency it's designed to be.
 * There are several other types of currency but only one is tradeable like Influence/Infamy and that is Candy Canes, which are only accepted by the Candy Keeper who appears during the Winter Event in exchange for various items. As such Candy Canes are only found on enemies associated with that event.
 * The completely non-tradeable currencies are: Reward Merits that can be used at merit vendors to buy rare items rather than trying to buy them off the player market, Vanguard Merits that are earned for defeating Rikti (after you join the Vanguard) and can be used at their base to purchase special items from them, and Tickets earned from playing Architect Entertainment missions that you can cash in at any AE building for anything from inspirations to the Uncommon or Rare salvage of your choice.
 * Characters who stick to one of the extreme ends of the alignment scale can earn Hero or Villain Merits. These allow for the direct purchase of rare recipes at a much lower cost. However, you lose all your merits if your alignment shifts, meaning that players farming for merits are limited to their home city, Co-Op Zones, and Praetoria.
 * In Little Big Adventure the same currency (Kashes) is used throughout the planet of Twinsun (partially justified by Funfrock ruling the world with an iron fist). The same is not true for in the second game, which uses a completely different currency, the Zlito (probably named after the Polish zloty). However, you can meet a collector who will take your items in as exotic curiosities, albeit for very little money. Furthermore, the  will only accept gems.
 * Not a videogame, but the gamebook series Lone Wolf somewhat subverts this by having multiple currencies. However, they have fixed exchange rates and are almost always given and used in multiples equal to an integer amount of gold crowns (the protagonist's "home" currency). For instance, 4 lune equal 1 gold crown, so most amounts of lune given are multiples of 4, and the exchange rate is usually given, as in "32 Lune (8 Gold Crowns)". Also, 4 lune take up the same amount of inventory space as 1 gold crown in the given rules despite lune being silver, so the game implies that silver, gold, and iron all have the same value! However, in a few areas, the currency you use for something matters a lot.
 * Meanwhile, the open-world gamebook Fabled Lands subverts this hard: trying to pay the Fair Folk with human money will result in you being unceremoniously picked up by a horde of terrifying goblins and hauled into the underworld, never to be seen again upon the surface.
 * Averted in the text based MMORPG Dragon Realms. There are three different types of currency of various denominations. After killing a goblin, it might drop one type of currency, but not one usable in the nearest town. To use it at shops, you would need to have it exchanged at a bank.
 * Most strategy games uses a common global currency for accounting purposes and ignores fluctuations in exchange rates.
 * Europa Universalis uses the ducat (a gold coin)
 * Victoria an Empire Under The Sun uses the £.
 * Though the British pound was (sort of) the universal currency of the age, what with the Brits having the biggest economy and most banks.
 * And Hearts of Iron simply uses "money" although it is symbolized by the $-sign. Money itself is not very useful alone, but it is used as a trade good to acquire more valuable materials like metal, crude oil, supplies, or fuel from other countries.
 * Justified in Homeworld 1&2 and the Expansion Pack Cataclysm. Your 'currency' for purchasing units are Resource Units, and actually are what you use to build items, and are only used once or twice to purchase technology from another spacefaring race, which you are told have been calculated very carefully to match their rates.
 * Medieval Total War (set in 1087-1518) uses the florin -- partial Truth in Television, as it was a standard coin throughout much of medieval Europe, containing 54 grains (3.5 grams) of gold.
 * Shogun Total War and its sequel use "koku" a Japanese unit of volume (about 278.3 liters), which historically was defined the amount of rice a single person can eat per year.
 * Master of Orion is a Four X game that uses the BC, probably for billion credits. Alien races use it too, judging by the trading screens. The base unit is large because you're running a galactic empire.
 * Ditto for the Galactic Civilizations games.
 * The game Deus Ex uses credits as the UN-controlled currency in the mid 21st century, with a few in-game articles discussing the ramifications of a totally digital economy.
 * Dollars are still mentioned at least once, however.
 * Pokémon is a special case - nobody seems to agree on what the English name for the P with two crosses is. Suggested names have included: Pokédollars, Pokémon Dollars, Poké, Poké Yen, Dollars, Pyen, and even Zenny. The only places where the currency is officially given a name are Poké in the Mystery Dungeon series, and Pokémon Dollars in the Colosseum games.
 * The Japanese games never have this problem, as the currency is simply Yen.
 * Which becomes kind of strange in Pokémon Black and White, which takes place in New York
 * In Transarctica, a game set in a post-apocalyptic ice world setting,, uses coal as a currency. The game is set on a steam train - making coal the most vital resource, keeping you from being crushed by the Evil Empire and freezing to death. Also, there are two kinds of coal - brown and black, black is the real currency, while brown is used mostly as fuel. You can use the black coal for a substantial speed boost, literally burning money. Must be a very funny economy, burning money on one side and frequently finding new coal mines on the other.
 * Averted in the Facebook game Mafia Wars, which tracks players' ill-gotten gains separately for each city/nation (dollars in New York, pesos in Cuba, rubles in Moscow, etc).
 * Crystals in An Untitled Story are accepted by anyone, outside of SkyTown included.
 * Soul Nomad and The World Eaters use Gig Points, the currency endorsed and backed by the one, the only, Indestructible Gig. It is never spent on anything in the mundane gameworld (and there's nothing you can buy anyway) - you spend it on hiring and employing troops, and buying edicts, decor and rooms, all of which can be considered extensions of Gig's powers. It's effectively the inverse of a global currency, one that only really matter to one person.
 * In Cyber Nations, players can choose one of several real-world currencies as their national currency, but it's really just for flavor: All currencies have a 1-1 exchange rate. Of course, talking about the in-game economy in which technology is traded for money is what the game wiki is for.
 * Obscure DS game Spectral Force: Genesis averts this, if simplistically. There are four major commodities (Gold, Jewels, Relics, and Livestock) and each nation uses one of the four as it's primary currency. During tax months, the others can be traded against your primary at a fluctuating exchange rate. Smart investments can make up a surprising amount of your income.
 * Obscure DS game Spectral Force: Genesis averts this, if simplistically. There are four major commodities (Gold, Jewels, Relics, and Livestock) and each nation uses one of the four as it's primary currency. During tax months, the others can be traded against your primary at a fluctuating exchange rate. Smart investments can make up a surprising amount of your income.

Western Animation

 * Possibly spoofed in the South Park episode "Pinewood Derby", with "Space Cash", used by some kind of planet confederation.
 * Ben 10 Alien Force seems to use a sort of Galactic Credit system, though it's rarely seen. A recent episode had the team given a gold-class "credit cube" (which appears to be nothing more than a 3-cubic-inch block), which apparently has no spending limit.
 * Like a credit card?
 * Snelfus on Cyberchase. The value of these doesn't seem to conform to any standard exchange rate--probably writer laziness rather than inflation. They look like euros in bill form.

Real Life

 * In Ancient Europe, the Roman Empire came about as close as you could get. Archaeologists are still finding caches of Roman coinage, and in fact the Roman "Denarius" was so common that it forms the root of many languages' word for "Money", and several modern currencies are named after the Denarius (the various Dinars, for example), including the penny (by derivation from the French denier).
 * Not to mention the British pound aka £ for Librum as in librae, solidi, denarii. Yes, until recently, the Roman standard still lived and thrived.
 * Visa is a pseudo-Real Life Example: they're accepted all over the world and in places you wouldn't expect, but they still use the issuing country's currency (usually dollars) as a basis for value.
 * Then again, they often aren't accepted in places where you would expect. Stores in Germany, for instance, tend to only accept EC and cash.
 * Until the beginning of the 20th century the global currency was gold (and, to a lesser extent, silver). All the different currencies (dollar, pound, mark, frank, etc) were weights of gold. So using and converting different currencies was generally trivial if the currency was known and trusted.
 * The British pound was a pound of silver, not gold.
 * But by Queen Victoria's day, the British pound was 1/3 of a Troy pound by weight. Regular pound weight = 454 grams; bullion is measured in Troy units, Troy pound = 385 grams.
 * The British pound (see £ aka librum, above) was a gold coin equal in value to a pound of silver. Sovereign weighs 1/4 ounce.
 * The internal conversions were insanely complicated before decimal currencies were common, though.
 * The "standard" silver coin in the 17th and 18th century was the Spanish eight-real piece (also known as the Spanish dollar and pieces of eight). As well as Spain, its colonies, and its trading partners (particularly the United States, which made it the basis of the US dollar), they were accepted as far afield as China and Australia (although the Australian ones were restamped with the British monarch's head and the value of 10 shillings).
 * There have been recent proposals by the UN to create a new global reserve currency for international trade. Whether or not it replaces the US dollar and the euro, or whether or not it gets off the drawing board, remains to be seen.
 * In modern (20th century) history, the American Dollar, the British Pound and the Japanese Yen took turns posing as universal currency. If the American Dollar stays weak for too long, the euro (€) is looking like the next contender.
 * There is something like an international reserve currency, the IMF's Special Drawing Rights. However, these are completely intangible and are only of use to governments trying (1) to peg their currencies (e.g. the People's Republic of China) or (2) to stabilize their currencies.
 * A number of survivalists (at least in the US) hold to the philosophy that in a scenario where civilization gets disrupted for a long period, people will refuse to accept modern paper and coin currency, and revert to gold as the standard trade currency. Other theories hold that gold, being useless for practical purposes outside of electronics (which would probably be nigh-impossible to make after the apocalypse), will fall by the wayside, and small, useful consumables (ammunition, aspirin, fuel, etc.) will become the common currency. The wise are betting hard on two-ply toilet paper.
 * In post-WW 1 Eastern Europe, cigarettes became the standard currency as confidence in money vanished.
 * Similarly in post-WW 2 Germany until 1948.
 * The US Dollar is one of the most common reserve currencies in the world, meaning that many nations peg their currency compared to the dollar. It is believed that there are more US Dollars outside of the United States than within.
 * A Cold War saying goes that Russians and Arabs hate the Americans, but love their dollars.
 * This is much less the case in the post-Cold War world; the US dollar is mostly still #1 but competes with several other currencies, especially the euro, but also the Japanese yen and several others. That said, the recent problems in the Eurozone and the fact that nobody particular trusts the Chinese mean that the US dollar remains the base of most of the global economy.
 * The euro started as an attempt to go in this direction. Initially, the 27 member states of the European Union each had their own national currency (the French franc, the Italian lira, the German mark, etc.). Currently, 17 of the member states use the euro as their national currency. As well as Montenegro and the Kosovo (who previously used the German mark).
 * Nothing. There are some schools of thought that believe that there will never be a global currency because it wouldn't allow enough flexibility when regional economies fluctuate. That was one reason the world as a whole left the gold (or silver) standard after World War II and allowed the different currencies to rise and fall in value against each other.
 * An example of this can be seen in the Eurozone. The current debt crisis in Greece, Portugal and Spain would traditionally be solved by devaluing their currency as a way to pay back their debts more easily and encourage foreign investment. However, since the euro represents the entire Eurozone, including Germany, which has a much stronger economy, the euro remains strong and Greece, Portugal and Spain are out of luck. For a while there was a lot of fear that Greece would go bankrupt, which would damage confidence in the Eurozone as a whole whether or not individual countries deserved it. A single currency is not without its risks.