EQ at first was actually better for farming than WoW currently is.
I believe they didn't have bind on equip or bind on pickup items until the planes. Meaning, all of the bad ass gear you could get and use - you could sell after equipping.
WoW doesn't have a huge market for rmt's on weapons or gear but rather gold. Where in EQ, the gear was actually more valuable than straight currency.
Based on this, I could find some gear that sold for more currency in-game than the gear would fetch alone on Ebay. Then I would buy more desired gear in-game and sell that on Ebay with that currency.
Specifically I would farm glowing black stones, which at the time sold for easily 10,000pp. The item itself would sell for $300+ on Ebay, but instead of doing that, I just bought a ton of items with the 10,000pp.
I was a fairly casual player for 6 months in EQ and quit shortly after RoK came out. In total I made around $1500, I even sold my character for about $250 at the end. Funny because they were basically naked or wearing vendor gear.