It was only a matter of time
Developers have been musing for years that Macromedia Flash could serve as a good, platform-neutral container for WYSIWYG text editing and formatting in a browser. Evidently, some of the newer hooks in Flash MX make this more possible than ever. One Flash guru has come up with an example, and it generates pretty clean XHTML. Doubtless others will follow. For our part, we'd like to see the textarea box disappear completely...
Try it yourself