Offline Blogging Tools let you comfortably write and effortlessly publish new entries to your blog. I personally like the easy to use Scribefire, a Firefox addon, but there are many others our there. Here is a shortlist…
Platform: Windows, Mac, Linux
This is an addon for Firefox so you need to be using Firefox (clearly)
BloGTK is a weblog client that allows you to post to your weblog from GNOME without the need for a separate browser window. BloGTK allows you to connect with many weblog systems such as Blogger, Movable Type, WordPress, and more.
WLW is a desktop application for publishing to blogs and works with almost any blog provider in the world including Windows Live Spaces, Blogger, WordPress and more.
Platform: Mac, Windows
Great for bloggers on the move. Qumana features include easy text formatting and image insertion, simple Technorati tagging, advertising insertion with Q Ads and more.