Leafnode is a news server, suitable for small, limited-bandwidth sites with only a few users (and useful for offline news reading). Leafnode keeps track of which groups are being read and downloads only articles in those groups. Leafnode has been designed to require no maintenance and to be easy to set up.
Usenet Downloader can be used to retrieve newsgroup articles from NNTP servers. There is a generic NNTP class that can retrieve listings of groups, listing of group articles, and the article headers and bodies. There are other classes that can retrieve listing of groups from several different sites and insert the listings into a MySQL database table. Other classes can retrieve groups stored in the database and retrieve articles of those groups from the NNTP servers.