Or specifically the mods? I'm playing a modified version of Dwarf fortress that takes place in the fallout universe. http://www.bay12forums.com/smf/index.php?topic=22554.0 There's also a cool Necromunda mod, I haven't played it in earnest yet since I don't have enough time to dedicate to a heavily modified version of dorf fortress.
I have it on my computer, and I've fiddled around with it a little. I didn't get too far, though. Great game, anyway.