Markets. Demand. Supply.
One thing about a virtual economy is that the quick feedback and response and the immediacy and flux of the economy is very evident. In the space of a day I have gone from penniless adventurer to moderate wealth as a "clay supplier."
A bit of background: several weeks ago my son came home from school very excited about trying a game some of his friends were involved with online: Runescape. Runescape is a virtual world, a MMORPG (Massive Multiplayer Online Role Playing Game). Runescape, as MMORPG's go, is strictly at the low end. It is a java-based online game offering a fairly cheap and relatively painless entry point for people who want to try the MMOG but don't want to dive into the more intensive involved Worlds of Warcraft.
Runescape is set in yet another fantasy world peopled with the usual beasts, monsters, quests, and magic — you know the type — with a selection of easy monster and creatures on which to hone your skills, and a selection of progressively more difficult quests that help to build your skill level until you can take on the bigger creatures and beasts. (Note: Avoid the Chaos Elemental. I named it the Ravenous Bugblatter Beast of Traal after it defenestrated me in the wild.)
The biggest problem in the virtual world is the same as it is in our real world: money. How do you go about earning cash to finance your adventures? It is relatively simple to earn small amounts of gold (chopping wood, mining tin, killing goblins, etc.), but after a time such make-work becomes tedious. Through nosing about, we managed to discover a source of magical runes that we could then sell in one of the towns for 70 gold pieces each.
Aha! Easy Money! So we thought. Each trek out to the site involved a laborious and intensive hike into the wilderness, a region rife with player-killers, generally high-ranking. A direct route was out of the question as far too many homicidal maniacs waited by the main road into the wilderness for some cheap kills. Getting to the site involved a very long and meandering route to avoid the many monsters and other players. Once you finally arrived, you had to daringly dart in to collect as many of the runes as possible, wait for them to respawn, and then collect again. In short, it was a JOB — dirty, dangerous and tedious.