try TheUniversal.
its a small free online 3d game with an active community of 50-100 players who all know each other and mostly get along fine.
the gameplay is sorta a mix of Subspace, Simcity/starpeace, Twisted Metal, and The Sims.
you have space trading, piracy, and combat.
there are servers with detailed economies to take part in where supply and demand play a big role in things, sorta like how simcity or starpeace is.
there is vehicular combat like in twisted metal
and on some servers there is hunger/thirst/death like in The Sims.
oh, and you can also download your own server to set up how you want. the servers are fully customisable. from the buildings, to the gameplay rules, to the vehicle behaviours. you can even change the color of the ground and sky.
check it out at
http://www.theuniversal.net
there is no other game on the internet like it.