The basic question is: do they work? What checks and balances does the game need to make sure they work sensibly? A bit of background is in order, I suppose. I'm currently writing an online game in which players can claim tiles as part of their nation, and surprisingly enough the aim is to become the biggest, most powerful nation. On some tiles are collectable resources, both surface (like trees) and subsurface (metal ores, coal and so on). The idea is that such resources (once collected), and processed products, are tradable: there is a public market where you can buy and sell at whatever price you like. (A little like Earth: 2025's, although with more goods types.) The resources are replenishing, in that if you mine out a resource in one place another will appear elsewhere on the world. However, the new resource won't necessarily be the same type as the first one; new resources spawn with a particular (fixed) probability distribution for the various types (e.g. 10% of new subsurface resources will be coal, 30% iron, or whatever). So I'm hoping that more in-demand resources will become scarcer and each item type will find a natural market value. The money used in market transactions will also be used in other aspects of the game – attacking, mining, prospecting and so on will all have costs associated with them, and large populations will provide income. These costs and benefits will be fixed, or at least not market-driven (they might vary with nation level and so on). So the currency should be grounded by that.

Hi,
this is extraordinary(well sort of anyway)
I had an idea much like yours for sometime now.
My suggestion was that the resources would be produced/extracted by population inhabiting those tiles , and the population expands according to fullfilement of its basic needs (first) and luxury needs (second).
Of course items should be bounded to areas just like in real life(e.g wood production available only in a forest, iron available only over a deposit etc).
Respawning not necessary(the maximal production limited by population size in the tile*population developped skill* /*if needed*/*input raw resources used in the production process.
skill would be evolving over time,decreasing when the pop.increase, increasing when new items are produced and staying constant with a decrease in tile population.
To make this work , those population tiles should be encouraged to make trade between them on short distances and maybe with a market place(or commercial areas).
Market places should establish commercial links between markets and allow both commerce with population tiles and between one market and another.
Markets places should be allowed to establish their prices(according to owing player which may be a NPC)but they must follow their interest -ballance needed.
Out of an originar soup,independent house tiles may unite and form a burg(create a market place by paying the costs).This burg may help create warriors/tanks etc.
Players should own at start one or some of these burgs(a tile is owned if you are the last to place a combat unit over it+an owned tile will obey the masters order:change production, recruit,limit production for a pop tile and set prices and economic policy for a commercial tile.
By the mid game powerful coalition of independent burgs might form.(even a player may adhere to one such coalition on economical(mostly trade and price-setting policies),political(production orientation,population limits settings) and military
(common attacks defenses,free passage for military units etc)

Obviously,this could even develop in a 3d scene.

Well, any economy will fall apart unless there is a continuous shortage of and demand for the final product. If there is going to be continuous production of these widgets, the only way to maintain demand is to also have continuous destruction of these widgets, for example by having them get worn out through use, be consumed to improve something else, or paid to a game-run store in exchange for something else.

Also, it can't be cheaper/easier/more interesting for a single player to carry out the whole activity of manufacturing than to buy the final product, or everyone will be a do-it-yourselfer and no one will be a consumer. But at the same time it has to be rewarding for some players to carry out some of the steps of the manufacturing process, or no one has anything to trade. There are three solutions to this.

1) Severely limit the initial supply of materials, probably by giving them out randomly, such that only the players who can get their hands on the materials by luck or trade can work with them. This is not a great solution because it minimizes the amount of game time players can spend harvesting and crafting, two activities which could potentially be fun mini-games occupying a lot of the player's time.

2) Make it cheaper to do in bulk. This will result in some players spending a lot of time crafting and other players spending little or no time crafting. This could be okay if you make sure your players who aren't crafting have something else to do instead, preferably which will create a final product the manufacturers want.

3) Make some players better suited to some manufacturing activities and others better suited to other manufacturing activities. This can be done as an aspect of character creation, as an aspect of location (if players are mostly confined to one location), or by time of day players are online. This could annoy players who find themselves unable or severely disadvantaged at doing a gathering or crafting activity they think would be fun and want to try. Another possibility here is to give players' the choice of which aptitude their avatar has, and the ability to swap this aptitude for a different one, but make the swap expensive or only able to be done once a week. Players would thus be limited to only one type of gameplay at a time, but can cycle through the various types of gameplay, which may increase the game's replayability.

Hmm. Well, my game isn't character based so some of it is not relevant to me (though I'm sure it will be to others redaing the thread!), but your advice is very useful, sunandshadow :). I was thinking of making the resources raw material for various streams of use – producing energy, equipping your army and so forth – all of which would take it out of the system, so I think I have that aspect covered.

I will have another think about how to make some players want to take up big-time mining, or manufacture, or whatever and make the market come into play, but my current idea is that the technologies you need to research to do such things well are relatively expensive (in money and in research times) and don't help with other disciplines. That way, if you want to be the strongest nation militarily you wouldn't want to 'waste' levels on researching Advanced Deep-Sea Drilling or what have you, you'd just buy the materials from someone who found that more fun than attacking people.

With reference to your point (1), the initial resource distribution is random throughout the entire world, but the world is large enough (currently 800,000 tiles) that all players will have an opportunity to find even rare resources.

The only proble with using expense to limit technologies is that it only works well for players who have been around a few months. n00bs can't afford to do anything and old timers have probably bought the ability to do everything.

EVE has a real problem with its economy because the macro-running cash farmers mine all the ore out of the rookie zones. Consequently, it's difficult for a newbie miner to make any money, so they give up on mining and turn to combat, since macros are terrible at fighting the NPCs, and that money is still available to players. This floods the NPC-killing market, so the low-level combat pilots turn to piracy to make their money. They quickly learn that the more experienced players can nuke them without much work, so they return to newbie areas and oppress the poor startup miners even further, which causes those miners to turn to piracy, and the entire game goes to hell in a handbasket.

The high-level economy of rare minerals and manufactured goods is thriving, though, and the high-level players really do use it to guide their trade and manufacturing operations. It works great as soon as you reach the level at which macro miners can't really influence it. But there are still too many pirates who can't see past stealing and fighting, because those were the only two game elements available to them in the beginning.

Bottom line: Make the economy accessible and useful to everyone, all the time, and they'll participate in it.

Also, have a few NPC organizations that can adjust their supply and demand to keep things tuned up while you adjust the availability and rarity of items in the background.