great XHTML/CSS design at openweb
openweb.eu.org has the best XHTML/CSS design that I've seen in a long time, including accessibility and style switching. It's in French but this shouldn't prevent you from enjoying the design.
And it's beautiful and readable.
I'm writing this here to remember to use it as an example. In fact I stumbled on it because they wrote about the many ripoffs that they see around the web, so it's certainly an example for many people already.