(EDIT: Don't know of EVE Online? This article sums things up nicely.)
In order to top my mistake of signing up for World of Warcraft I recently signed up for EVE. Warcraft was getting too repetative and simplistic. I'm sick of the hand holding. Its too easy. EVE offers a much higher level of complexity, player control and open ended gaming. Combat? Mining? Trading? CEO? Spy? Con-man? Scientist? Trader? Manufacturing? Explorer? Bounty hunter? Whatever you want. No classes. No levels and experience points (and thus no grinding or level cap). A player controlled market. Player built space stations, ships. Player controlled star systems. And if your ship gets destroyed... well, hope you had insurance.
I'm also sick of learning I have friends who play WoW only to find they're on a different server shard. The fractured universe is, I think, Warcraft's biggest drawback. EVE has just one universe. 15-20k people playing together at any given time, largest ever. This, plus the much steeper learning curve, I think makes the EVE community a tad more mature.
So... anyone play EVE? Its a big black out there and its a big, complex game to learn. I'm on as Stainless Rat (just as soon as I put my PC back together).
And its written in Stackless Python! Wow! An enormous, graphic intensive PC game, client and server, written in a dynamic language. Gives me hope, folks.