What is a Gold Sink?

Gold sink is an economic process by which a video game's in game currency ('gold'), or any item that can be valued against it, is removed. This process is comparable to financial repression in real economies. Most commonly the genres are role-playing game or massively multiplayer online game. Gold Sinks are commonly used to reduce inflation when commodities and wealth are continually fed to players through sources such as quests, looting monsters, or trade.

Gold sinks are commonly called drains or gold drains. They can also be associated with item drains. The intent of a sink is to remove added value from the overall economy. For example, in Ultima Online, items that were placed on the ground would be gathered by the server. This form is referred to as decay or garbage collection.

Economies in virtual worlds operate very differently from those in the real world. Passive gold sinks may be in operation at all times to slowly extract value from the game. Players are usually more willing to accept this method of sinking. Passive sinks would be item degradation, consistent taxes, or decay. Active sinks are aggressive actions by the programmers to remove excessive value. These can be changes in the severity of the passive sinks, such as higher taxes or faster decay. But more effectively, an active sink can be the selling of unique items whose intrinsic values are much lower than the selling price sold by NPC vendors.

List of Gold Sinks and Ideas for UO Evolution

Taxes. Charge fees for maintaining a character in proportion to their property, income, or purchases. Although this would be fairly easy to implement, it is politically explosive.

One corollary to this idea is to have imperfect tax enforcement. If players are randomly taxed (like an IRS audit) in proportion to their wealth there might be an interesting wealth gamble which takes place which reduces the overbearing perception of a tax.

House insurance?

Storage Fees?

Maintenance on real-estate. Make houses or other capital goods deteriorate in such a way that repairing them must be done by an NPC. Adding a similar PC repair skill would only help the hoarding problem if it consumed some resource however what that resource would be is unclear.

Natural Disasters. Clear out hoards with an occasional storm or quake.
Maybe all the players must complete a quest or the bad thing happens!

Lotteries. Like any real-world lottery, rig the numbers so that it collects considerably more than it pays out.

Consumables. Currently, magical reagents are one of the few consumables. It is just a matter of design to think of more items which provide a useful function but which consume a resource. Increasing the consumables is by far the most politically feasible drain because the players feel they are getting something for their cost – i.e. it isn’t a tax.

Indulgences. Services such as ‘red hair dye’ which players are willing to pay for but which don’t cost server resources. Extreme examples might be titles; for example, 10,000 gold buys a character the title "lord".

Recycle bins. Provide places where players can dump old junk for cash. This will inflate the gold economy but reduce server overhead (since gold requires fewer server resources then non-gold items).

Capital good depreciation. Make items which are used to produce other items such as forges, houses, tools, etc. degrade more dramatically with use. This is slightly more politically acceptable than other degradation rules because these items are producing profit while they are functional.

Auctions. Sell houses and items though auctions instead of fixed prices. This would be particularly helpful in reducing gold inflation.

Market fees. Specialized taxes for places such as large marketplaces.

Make each player "born" in a random city, each month there is a tragic event that effects players born in that town, like invasions, earthquake, war tax etc

To offset this maybe make good things happen also, like the chance cards and community chest cars in the game Monopoly

Item Insurance

Vendor Fees

Raffle Stone

Quests requiring a certain amount to continue with the task at hand. This is offset by quest rewards and items that may be resold.

Fees associated with NPC services and tasks.

Fees associated with travel and convenience.

Crafting, often requiring an initial investment and a continued chance of failure.
Items may be crafted at a loss to increase crafting skill.

Auction House Fees

Taxes

Gold Limit per Account in Ultima Online

Rent an item like an ethy mount for 1 week

Gambling casino

Poker

Gold to trigger events or champs?

Create deco to buy


List your gold sink ideas?

Some interesting ideas, 1 or 2 of them even sound somewhat benevolent. 

For better or worse game design has changed a lot over the years to be more rewarding and gratifying to players, so when I'm thinking of ideas for new or improved systems they seem to lean that way. Actually I think one of the reasons it might've started to go in that direction is 'meta-gaming', players figuring out ways around punative measures and subsequently benefitting over those who simply lack the same information, something which I've personally observed in pretty much every online game I've ever played. 

The natural disaster idea sounds like it could have a lot of potential and is similar to an idea of mine (the benevolent version) where you'd sacrifice gold and or possibly items to a shrine/god and when the theshold is met a server wide buff, which could be as simple as luck, or perhaps an event could trigger. Could also be a nice community builder as many players coordinate to enable.