In every game that I play, I have this tendency to gravitate toward the market or 'trade' side of things. In some games, the economy is relatively simple, or ultra controlled. In others, it can be somewhat more complicated.
After playing Lord of the Rings Online for a few months, (off and on) it was no big surprise to me when I started hanging at the auction house, scanning for trends and researching ways to make some quick gold. I admit, I wanted a deluxe house with all the trimmings, so I had some motivation for making some easy gold.

Unlike the EVE Online economy, the LOTRO economy is much more simplified. You still have the ability to produce goods out of raw materials and then sell in an auction type setting, however, you are not given many options. You are limited in the number of auction houses available in game (usually no more then one per region) and all auction houses tie into the same 'pool' of auctions. (So what you see in the auction house of one region is exactly the same for all other regions.)
Also, there is no concept of location in the economy. You bring your product to the auction house, put it up on a post, and someone could buy it in a completely separate auction house and immediately have it show up in their mail box. Therefore, you have one mass economy, and not one that is separated by in-game locations.
Also, because there are multiple servers in LOTRO instead of all players sharing one identical world, the economy could be different depending on what 'world' you're on. The supply and demand couple be different based on what type of players are on the server, and since you can not transfer your characters between worlds, there's no way to use this to your advantage or sell things cross-worlds.
After playing with the markets and economies in several mmorpgs, I think that several things could be done to improve the one in LOTRO: