After Rick Segal mentioned Windows Live Writer, I figured that I had nothing to lose if I gave it a try.
The problem with that thought is that I did have something to lose. And lose it I did. I lost my belief that Microsoft couldn't produce a program that is worse than any other alternative.
I don't like to unnecessarily hate on Microsoft, but I find their products to be absolutely terrible when compared with sufficiently advanced alternatives. In the case of Windows Live Writer, there is no alternative.
A few folks have pointed out Mars Edit and other offerings (on OS X, as that is my platform of choice currently) but they really aren't as good as Live Writer. Even under Linux I couldn't find anything that is just better than Live Writer.
It still isn't perfect, but it works extremely well. Now my only hope is that Microsoft will lose something... the irritating need to bundle a staggeringly large amount of irrelevant software with Live Writer. Until they do that, I don't think I can recommend Live Writer to people who won't just blindly click "Continue" without seeing what other crap they're installing. If you do read before clicking, definitely check it out.
It seems to be working fantastically with Movable Type 4, but I still need to figure out how to manage static pages.