I'm really impressed with Ecto, which is a helpful GUI program for maintaining your blog (such as this Typepad blog) for both Mac and Windows. Obvious things, such as a preview mode, and a type-as-you-go spell checker are nice, but what really impressed me was how graphics are handled.
I just drop a graphic on the text, it's then replaced with HTML for that graphic. You can change properties of the graphic, but what's nice is that it'll then upload the graphic for you to Typepad, a process which is quite tedious if you use the Typepad web site.
You can edit in rich text mode or HTML. The rich text mode works oddly, so I prefer the "know what I'm getting" html mode, which works fine. A wonderful "url with clipboard" feature automatically HREFs the highlighted text with the URL currently on the clipboard.