Just noticed that the NewzCrawler RSS Reader not only reads feeds but also Usenet Newsgroups and the Web.
The other interesting features is that it has a comments bookmarklet (via Comments API) to make comments on posts from your RSS reader…it also has a WYSIWYG editor to make posts from your RSS reader client to your blog.
Write posts offline, without opening your browser, then hit publish and it will send the post to your blog…other advantage is the WYSIWYG features are more expansive on these dedicated editing clients.
Some offline blogging editors:
qumana (5 days to go)