Auxilium
Cobblestone King
Mars Effect!
http://marseffect.net/
GAME FEATURES The game is still very early in development, but here is a list of things we hope to include:
Hard science fiction.
Lots of engineering.
Fully working computer system.
Space battles against the AI or other players.
A game ending that makes sense.
Abandoned ships full of loot.
Waist high walls.
Seamlessly landing on planets.
Advanced economy system.
Mining, trading, and looting. - Notch
http://marseffect.net/