4) Eve Online

Eve Online Industry Trailer

Many centuries ago, humanity located a natural wormhole and used it to settle a new region of space, but the wormhole eventually collapsed.  Mankind’s original home is now all but myth.  In Eve Online, players build their own empires by controlling starships in combat against rival leaders in industry. While Eve Online has frequent and heated combat, it is also a trade-centered role-playing game; you must locate, harvest, and process resources you can then use in negotiating trade deals with other corporations. 

Massive Space Stations Offer Trade and Ship-Repair Services

You’ll want to master the trade aspect of this game so you can afford all the modifications and upgrades you want for your ships.  Taking part in trade affects the economy whether you buy or sell, and savvy economists can manipulate the trade world to their advantage.  There are dozens of expansions available already, and many more are scheduled.