Wallet of Holding

""100 pounds of gold for a house? How does anyone make rent without a wheelbarrow?""

- The Dungeonomicon

In most modern video games - RPGs in particular - the principle of Money for Nothing strongly applies, to the extent that it's not rare to end some games with a cashflow in six or more digits. And several of these games depict money as collectible gold pieces. Tie these together and you have the Wallet of Holding, where a quantity of gold which would in reality amount to several tons (five million 24kt gold coins the size of the British fivepence piece would be over 41,000 kilos) and take up a colossal amount of space (the same amount would cover a football pitch) tucks up nice and neatly into a - completely disconnected part of the inventory where money takes up no space or weight.

It has a tendency to be more prominent in games where you have a limited inventory or carrying capacity for objects.

This is usually an used as an anti-frustration feature, unless the game is specifically trying to keep you from amassing too much wealth at once as part of an Anti-Grinding feature.

See also Bag of Holding, Hollywood Density.

MMORPG

 * In World of Warcraft Gold coins can be carried in infinite amounts. Gold bars, on the other hand, can only be carried 20 per stack. Let's not even get into the fact that a gold bar is only worth 6 silver (0.06 gold)…
 * Not only can you carry an infinite number of gold coins, you can always make change. If you have 6 gold, and you give 50 silver to another player who's carrying 7 gold, you end up with 5 gold 50 silver in your pocket and he ends up with 7 gold 50 silver. Where did those 100 silver pieces come from? Likewise, if you're carrying 2 gold 90 silver, and you loot 20 silver from a monster's corpse, you are now carrying 3 gold 10 silver—not 2 gold 110 silver. Like the Runescape example below, the amount you can carry is capped only by the signed 32-bit integer used to store it.
 * In RuneScape gold coins, or gp, are a weightless inventory item limited in quantity only by the game engine. The limit comes out to 2,147,483,647gp.

Roguelike

 * Angband plays this perfectly straight. By the time you win the game, you will have millions of gold pieces, which weigh nothing. Stranger yet, you can't drop it in your home or anywhere else, even though some monsters can steal money.

Role-Playing Game

 * The fact that Final Fantasy XI has this frustrates players to no end, as while you can hold millions upon millions of gil as soon as you start out, you have to jump through about 50 hoops to upgrade your 30 on-character and 50 at-home inventory spaces.
 * Played perfectly straight The Elder Scrolls: Morrowind. Septims are quite large gold coins with, apparently, zero weight. More amusingly, the developers only bothered to make discrete models for dropped gold up to 500 coins; which means you can have a 500 coin pile, and a 300,000 coin pile, both of which appear identical in-game.
 * Averted in The Elder Scrolls: Daggerfall, where money had a weight. The game had an extensive banking system to allow players to transfer their wealth into notes of credits.
 * Fallout and Fallout 2. In the first one, the currency was Bottle-caps. In the second, there are actually 'coins', represented as physical bits of metal. In both, everything else in your inventory has a measured weight, and your carrying-capacity is limited. In both, your money is entirely weightless.
 * Not everything has a weight; there are plenty of items, such as stimpaks, rad-away, beer bottles and buffout drugs that have a zero weight. Which means that at the end of the game, if you have some basic economic acumen, you'll be carrying hundreds of syringe-like stimpaks, dozens of bags of anti-radiation medicine, and maybe a few hundred bottles of beer, all of which take up no weight, and apparently fits neatly in your back pocket or wherever you wear things. Of course, you can also carry five flamethrowers and a minigun without a single bulge in your clothes, so...
 * Fallout 3 stays squarely with its predecessors on this one. Bottle caps are weightless. Most health items (but not food) are weightless. Ammo is weightless. That's right, a motorcycle helmet weighs 2 pounds, but those 50 mini-nukes in your back pocket? Weightless.
 * Fallout: New Vegas continues the trend, except the ammo will have some weight in Hardcore mode. However, the updated crafting system leads to some weirdness, like empty syringes having weight, but not the stimpaks you can make from them.
 * Neverwinter Nights most certainly isn't a subversion. You have an inventory weight system, sure, but gold isn't part of it.
 * And likewise Mount & Blade. Oddly enough, you can store your excess items in chests and these chests do have their own money counters, but there's no way to actually transfer the money into them…
 * Baldur's Gate. Gold is weightless, and plentiful. So plentiful, in fact, that you wonder why assassins risk their lives to kill you for 50gp when all they need to do is walk into a few noblemen's houses and rifle through their drawers.
 * Also, gems and many items of jewellery are useless other than to sell for gold, but they take up inventory spaces.
 * Wizardry. Gold is fantastically plentiful. And there's not a whole lot of places to spend it at.

First-Person Shooter

 * BioShock (series) limits how much money you can carry to $500. When you do find money in the game, it's as $1 notes, so I suppose the game is being pretty generous in letting you carry that much cash with you.
 * In the sequel, researching splicers will somehow give you an "increased wallet cap."

Hack and Slash

 * In the original Diablo, 5000 gold coins would take up an inventory slot, which led to a glitch where you can't buy the best armor in the game because you can't hold enough money. An item added in the expansion to the game doubled your gold capacity. All subsequent versions eliminated this, although Diablo 2 still caps the amount you can carry.

MMORPG

 * Averted heavily in Mabinogi, where money is collected in money bags that take up inventory space. These bags can only hold a certain amount, meaning you can end up with quite a few bags in your inventory. The one blessing is that you can buy a bag that holds an infinite amount, and money is fairly hard to come by.
 * EverQuest money has weight; for this reason, a lot of transactions took place near banks because the amounts of money needed for some trades would weigh you down so much that you couldn't move. The banks will also exchange your lower-valued coins for more valuable ones.

:MUDs

 * Averted in Bat MUD, where every coin weighs exactly one gram. There are a whopping 11 different types of coins, with the most worthless having the relative value of 0.01 gold coins, and the most expensive having the relative value of 500 gold coins. That means, if you are carrying money worth 80000 gold coins, it can weigh anything from just 0.16 kilograms (a small pile of mithril coins) to eight metric tons (8000 kg, a COLOSSAL mountain of mowgles coins, an amount which probably no character in the game can carry). If you deposit it all into a bank and then withdraw it, you get 80000 gold coins (80 kg) regardless of what kind of coins you deposited. Shopkeepers also accept all types of coins, and generally pay in gold coins. As a peculiar quirk, if you are only carrying highcoins, and you get robbed by a thief, who robs a random sum measured in gold, the thief will sometimes pay you small coins in exchange.
 * Played straight and averted in a variety of MUDs. Some games have multiple coins with varying weights for them, others have weightless money. Averted more often in Fantasy settings than Science Fiction settings.

Roguelike

 * Ancient Domains of Mystery: 1000 gold pieces weigh 1 stone (Which conveniently is 50 grams or about 0.11 pounds instead of the usual 14 pounds or about 6.3 kilograms). Your inventory can hold unlimited items, but if you collect enough gold (or anything else), eventually its weight will start to become a problem.
 * Nethack has gold Zorkmids as currency, which do have weight. Players looking to boost their endgame score by accumulating wealth are advised to convert the gold into gemstones to avoid getting so weighed down they can't climb the stairs.
 * In Scarab of Ra, the gold you collect while exploring the pyramid does slow you down... but wherever you see the words "Bank of RA" written on a wall, you can magically deposit it into your outside-world bank account. The net effect on realism is actually negative.

Role-Playing Game

 * In Albion, gold coins have a weight. It is low, but definitely noticeable, especially when you try to cash large amounts of high-level loot.
 * In the Ultima Underworld games, each coin weighs one tenth of a weight unit, placing quite a restrictive limit on the amount you can carry.
 * Arcanum coins have weight, as do all forms of ammunition, though an unlimited number can be carried in a small stack in your Grid Inventory.
 * In Spiritual Successor to Betrayal at Krondor, Betrayal in Antara, money (like all items) is weightless; but it is stored in a separate limited-space inventory, so most likely the protagonists will have to store excess money in chests. For some reason, money shares this separate inventory with the party's food.
 * In the sequel to Betrayal at Krondor, Return to Krondor, gold is heavy, but the characters always buy small low-quality gems when they leave a town, so that wealth is easily transportable. But if you don't visit a town for a while, you have a problem...
 * Money in the old Mac Shareware RPG Realmz had weight, and for this reason it could be exchanged from gold to gems for a fee at any business. This was rendered less dire by the introduction of banking, which allowed excess money to be stored at certain businesses, whereupon it could be obtained at any other banking business in the scenario, but it was still necessary to load up all your net worth in order to play the same characters in a new scenario.
 * In the Quest for Glory series, money does have weight. This can cause problems in the earlier games, where it is possible to acquire enough gold to take up a significant percentage of the weight you can carry with your relatively low strength without there being many useful items you can spend it on.
 * The various The Legend of Zelda games have an upper limit as to how many rupees you can carry at any given time. In later games, you can acquire larger wallets with a greater capacity as you go along.
 * Although, many games include higher-value rupees, such as Big Green, Big Red, or Silver rupees which are bigger than your head. That is this trope being played straight as an arrow.
 * The old Dungeons & Dragons Gold Box games averted this. Fortunately, it had a share option, which would divide the money among your party members based on their carrying capacity.
 * Money has weight in Super Hydlide.
 * There is a third party Fallout: New Vegas mod averting the bottomless wallet trope.

Simulation Game

 * Dwarf Fortress: If you make coins, then your dwarves apparently spend a huge amount of time walking to the coin stockpile to pick up their pay, carrying it, taking it home, and then going home to get some when they want to buy food or whatever. But… if you don't make any coins, then they all just remember their bank balance without it being represented physically at all.

Tabletop Games

 * GURPS gives a weight for coins, albeit it advises the GM to gloss over it. Also notable in that the Dungeon Fantasy points out that a good challenge for the players would be how to handle the logistics of transporting the loot they find.

MMORPG

 * In Dungeons and Dragons Online coins are weightless, but there's no automatic conversion. Copper are copper, silver are silver, etc.
 * If that used to be true, it isn't anymore. Coins change at a certain arbitrary value to a size up or down.

Roguelike

 * Averted in Castle of the Winds where cash has weight and doesn't automatically convert. Played straight in that it has no volume. And played straighter yet justified when you hit town and just dump the stuff at the bank in favour of a letter of credit.
 * In Assassin's Creed II and Assassin's Creed Brotherhood, there is an upper limit to how much money your treasury/bank can hold at any one time, which is a function of the value of your collections/renovations. Any amount earned above that is pocketed by Claudia or the bank. However, there is no upper limit to how much money Ezio can carry on his person. Meaning that Ezio can run around the rooftops of Rome without a sign of encumberment with half a million florins in his pocket while his bank vault is overflowing with a mere 80,000 florins in it.

Simulation Game

 * Partial aversion in the Animal Crossing series. Your wallet can carry a very healthy amount of money, as in 99,999 bells. However, it starts taking space in your inventory after you hit the cutoff point: 30,000 bells per slot in the GameCube game or 99,000 bells per slot in the DS and Wii games. Very few things cost tens of thousands of bells or more, and in the Wii game, most of those can be bought with a debit card that accesses the player's bank deposit.
 * In Dwarf Fortress Adventurer Mode, stacks of coins have weight based on quantity, rounded to the nearest Urist. Many stacks of double-digits or more will have weight appreciably increasing with the success of the adventurer. But the same coin could be have 0 encumbrance, if they're sorted into blindingly spammy single-digit stacks.

Tabletop Games

 * Dungeons & Dragons: Depending on the edition (and the Dungeon Master, as always) D&D either plays this completely straight or does not, by core rules, support it. By standard, 50 coins weigh a pound. This is regardless whether it's copper, silver, gold, platinum or steel, and whether it's freshly minted, taken from an ancient hoard, or received through wishing magic. At a certain point many players won't bother with cheap copper (unless they have quick access to money exchangers or are just that greedy). Gems and artwork treasures have a full selling price, so they can work pretty well as a money alternative. Sometimes you may even hold on to particulary expensive weapons and armor simply because they weigh less than the money you'd get for them. (Which makes a certain sense, as the merchant who'd want to buy a +5 lance is also the person who'd be likely to sell the stuff you want to buy.)