1. Outlook Express. This is the traditional news reader, it works fine on Windows, you never have any problems with it.
2. Pan. This is based on gtk, it is almost as great as Outlook Express, but it need tough build on Mac OS X.
3. slrn. Should we read news on a terminal? maybe that's the one. Terminal can have a lot of brilliant applications, but not do a good job on web browsing, news reading.
4. MT-NewsWatcher. It is free, but it is NOT in a good shape with GUI.
5. Unison. Just download it and get it a try, which is brilliant! It tell me what news server from my ISP I can use, great work! And I have no trouble to startup, love it.
Ususally I would try Pan, because it is free and it can be used on all platforms, just like firefox. And I am not willing to pay a comercial newsreader, such basic tool should be free, but I am considering buy Unison.