NetHack is a dungeon adventuring game. It features complex ASCII graphics and more depth and detail than similar games. Diablo is a good example of a game which owes a lot to NetHack - it is basically a much-simplified version of NetHack with fancy graphics.
Related categories 1
Official site. News, guides, links, and both source and executables for several platforms.
Google Groups: rec.games.roguelike.nethack
Discussion group for Nethack enthusiasts.
Version 3.2.2, Japanized. Features a new class, source, and executables.
The NetHack Dungeon
Hall of fame, tips and tricks, spoilers, and other files for the 3.2 release.
The NetHack Index
Annotated directory of spoilers, variants, patches, utilities, servers, reviews, and other useful information.
Dictionary, world map, and play statistics.
Wiki containing game information, spoilers, and other information related to NetHack, and games forked from it.
Frequently asked questions about the game, its Usenet newsgroup, and related topics.
Yahoo! Groups - thenethacklair
Gameplay discussion group. Free membership required to participate.