rec.games.roguelike.nethack is a USENET newsgroup devoted to
discussions about NetHack. Spoilers, advice, and tales of triumph are
good topics for discussion.
USENET is the world-wide system of newsgroups for the discussion of just
about any topic imaginable. Like NetHack, it's older than "the web".
One of many places to look for more details is
Usenet Software: History and Sources - but you don't need to dig
into it to use it.
Obviously it depends on your ISP and your newsreader (which may be a standalone
program, a site you visit with your web browser, or you may use the newsreader
built into your web browser). Check your ISP's web site or documentation and
look for "USENET", "newsgroups", "news", or
"nntp".
Many private and public servers or access points are available either for free
or for a fee. Check your school or business, ask your friends, or do a search.
Or try one of the services listed here (disclaimer: I don't use these, NetHack
is not associated with them, and their presence on this list is not an
endorsement of their services):
There are many, many newsreaders available. Most web browsers, including
Netscape, Mozilla, and Internet Explorer (using Outlook Express) have
newsreaders built in. In addition, some standalone newsreaders include: