Just wanted to throw up this link. Another user asked about the WMD Editor as a WordPress plugin, and I didn't see any readily available, so I threw one together real quick.
I'm not exactly a plugin master, so all this really does is link the JS file in the head of your template. Any suggestions on improving this plugin and constructive cristicism are appreciated.
I've only tested this in WP 2.5.1.
P.S. - Please excuse the website, as it's still coming together...