The maker of Dwarf Fortress has released a linux native port:
The Dev log has links to the forums and the program.
If you haven't tried dwarf fortress, it is a complex social sim where dwarves try to eek out a living and fend off nature and goblins by digging a fortress into a mountain. The UI is rough around the edges, but once that is overcome the game is fantastic.
You can use your imagination to:
-Build your fortress inside volcano calderas
-catch dragons and trap goblins and force them to fight in arenas
-filter the ocean to catch mer-people and then slaughter their offspring to make bone totems to sell to traders
-pump water into your Dining Hall to make a recurrsive waterfall
Dwarf Fortress is still in alpha stages and the creator is constantly making changes. Donations are requested.