I've been playing with ecto the last couple of days, which I really like though I'm not yet sure what the specifics are that make it a good and useful program. ecto is a desktop blogging client that lets you manage your blog entries from, well, the desktop:

With ecto you can write and manage entries for your weblog(s). The advantage over using your weblog's control panel is that you can compose entries offline and use the extra features ecto offers, such as spellcheck, creating links, attachments, and much more. ecto is designed to make blogging much more easier and yet give the users as much power as possible to manage their weblogs.

It's more WYSIWYG-ish than the regular Movable Type interface (and also works with Blogger, Typepad, WordPress and others). It lets me capture things from both my browser and my news aggregator. And, it lets me easily work off-line. It also lets me edit posts I've already posted and makes it easy to maintain multiple blogs without typing in new urls or changing pages.

I'm using ecto on a Mac with OSX. My understanding is that it was originally written for the Mac. I tried it once before on Windows and couldn't get it to work very satisfactorily but I'm pretty sure that was right when the Windows version first came out and it looks like it's improved significantly since then. ecto offers a two week trial version. After that it can be purchased for under twenty dollars.