Any good browser based WYSIWYG editors?

Nuvo

Hello.
As I've been working on the ACP of my Rails app, I've been thinking about changing from the slightly less than perfect Textile and Markdown implementations that Rails has to a WYSIWYG editor.
I've been searching for one that will output XHTML compliant code to start with and I came across a few different options.

Xstandard Lite:
Xstandard is a commercial editor for websites and desktop applications, but there's a free Lite version as well.
It is designed to output XHTML 1.0 compliant code, which is what I wanted, but it's not really web based, which is an issue on pretty much any website I could mention.
The problem is that it's actually a plugin for Internet Explorer and Firefox under Windows or OS X and this doesn't really suite my needs at all (I use Firefox & Opera under Linux).

TinyMCE:
Come on, it's TinyMCE!
My only gripe with this is that getting it compliant requires and awful code block from their forums and that block makes the already intrusive JavaScript init block you have to put into your site incredibly oversized and ugly.
It does generate compliant XHTML once you've worked out where any problems are coming from (extended valid options suck), but it'd also be nice if it's pop-up windows didn't show attributes such as target for links if you're not allowing them (target isn't part of the XHTML 1.0 standard).

WidgEditor:
This tiny little thing is pretty good.
It's built to do XHTML 1.0 code and there's no code to put into your page other than a link to the JavaScript and CSS file (you could copy the CSS to your main file though) and a class on any textarea that is to be converted, meaning it's incredibly painless to get it going.
It has very few tools though as it's limited to bold, emphesis, links, images and lists, though a source mode is available (like a plain textarea).
The main issue I've had with it is that sometimes, if the editor is empty, you have to go into source mode and type in order to get it to focus so that you can actually write in it.

Does anyone know of any small, XHTML capable editors that are free?