If you want a good online game try Armada Online.
Its a space ship MMO. The game Armada use to be on dreamcast...then the DC failed.
The makers bought the rights and are now making an mmo. Its still in alpha so alot of the content still isnt implemented but it is still a good game.
Armada Online
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Best Free Games To Download Online
Has a list of a lot of free online games.