JBlogEditor, as the name suggests, is a blog posting tool built on Eclipse Rich Client Platform. Currently it works only with WordPress, Blogger and JRoller. It has got a HTML editor with code assist, support for categories, post preview, multiple blogs, formatting tool bar and draft support.
I tried it out with WordPress. It works well behind a firewall/proxy server. It is just a 0.5 version so it still requires a bit of a polish. For instance after successfully posting it shows a dialog with the number “4” and no other text. It also lacks some features like image/binary content upload. But it shows good promise.