Newzbin (paid usenet search engine) closes due to legal action
newzbin.com
newzbin.com
"One of the main technologies produced is an XML-based file format called NZB files, which contain a list of messageIDs that are related to specific postings on Usenet. Through the use of these files, Usenet clients are able to directly download material from Usenet without having to pre-fetch the headers for the target group. Thus, the main benefit of the direct link is improving the efficiency of Usenet binaries. It is technologies such as these that are increasing the popularity of Usenet for file sharing."
http://en.wikipedia.org/wiki/NewzBin
It seems their crime is indexing binaries. This does nothing to stop file sharing through Usenet, just ever so slightly impedes access.
Then there's the bit where as a messageboard it's long been superceded by forums and other forms of communication.
Then there's the bit where according to wikipedia over 5 terabytes a day of binaries get posted, and although I have no evidence somehow I don't think that's linux isos.
Then there's popular culture which constantly touts it as some kind of exclusive club 'the man' mustn't learn about because that way it'll stay 'safe' to use.