I usually use Daniel Jalkut's MarsEdit on the Mac to edit my posts here. It's a sweet little program that works with Blogger, Wordpress, Movable Type, and most other blogging platforms. It allows offline editing, and greatly simplifies posting images from Flickr and so forth. I used Ecto for this for years - it's still around and works on Windows and Mac - but MarsEdit 2 is my tool of choice on the Mac. A number of friends have been raving to me about the free Windows Live Writer (WLW), though, so I decided to try it this evening. Wow!
For all the things Microsoft has done wrong (cough Vista cough), Windows Live Writer really is done right. It's designed for Microsoft's own blogging platforms, of course, but it also supports Wordpress, Blogger, and the usual suspects.
WLW gives you a live preview based on the actual blog style sheets - impressive - supports embedding of pictures, video, maps, and more, and best of all supports plug-ins so other blogger/programmers can extend it (with Flickr support, for example).
The picture embedding interface is an example of how rich this program is. It doesn't just upload an image and insert the relevant HTML, it has built-in picture editing tools, too. You can add a drop shadow or photo frame, resize, rotate, and adjust contrast. Or add special effects like sepia toning, watermarks, and more. All without leaving WLW.
There are some negatives. WLW embeds a lot of HTML into posts, which means they're harder to read if you edit them with Wordpress's own editor. And some of the layout defaults aren't great (notice the left justified "Sample Map" above). But considering this is only beta 3 there aren't many rough edges.
I've always been really impressed by the Windows Live tools - these guys may be doing the best programming at Microsoft. At least there's some consolation for those of you stuck working in Windows, and I wouldn't be the least bit surprised if Daniel doesn't add some of these features to Mars Edit, too, which will make Mac folks a little less envious.