[bananicorn]

DCSS = Dungeon Crawl Stone Soup

ADoM = Ancient Domains of Mystery

Cataclysm DDA = Cataclysm Dark Days Ahead

I swear I didn't make the first one up ;) Edit: ah well, you got your answer already^^

[zenorogue]

"Stone Soup" refers to the Stone Soup folk story, where people contribute their supplies to make a great soup for everyone (it is developed by many people who contribute to the open-source project started by Linley Henzell as Linley's Dungeon Crawl).

Still a better name than NetHack (which is not a game about hacking networks... "Net" just refers to collaboration over net to improve the game Hack). There is also BrogueCE ("Brogue Community Edition").