WYSIWYG Blog Editor
I've a visual guy, so I really like to see what my blog will look like while I'm writing it. I've used some blog editors in the past, but had problems with them. Today I just discovered a really, really nice blog editor, called Windows Live Writer.
What's really cool about this editor is that it works with my Blogger, which is what I use for my blogs. And even better, it pulls down the template that I have on my site and let's me see exactly what my blog entry will look like while I write it. The colors are the same. The borders are the same. Etc. Very cool!
They also have an SDK, so it looks like there is a certain amount of customizing you can perform with plug-ins. I haven't looked at it yet, so I'm not sure what you can do.