I nominate Yvette's Wedding Dresses, of Panama City, FL. It's obviously terrible in so many ways, but I browsed a significant amount of the site because there's actually a fair amount of content there, if you could ever possibly read it (oh and viewing the source code doesn't help; go ahead and try). I also read nearly all of Gene Ray's ongoing treatise, the illustrious and famous TimeCube.
We've all got to remember that as good as the web gets, as good as we get as web designers and web developers, there's always the indisputably cool notion of someone knowing absolutely nothing about those things, and producing something that's useless as an informative website but may live forever as a creative expression in the medium of web. I'm sure the TimeCube is already there, for a lot of people (Gene even spoke at MIT about his theories, to the amusement of everybody present but him). Now that Geocities is defunct, we may see fewer and fewer of these endangered websites. Let's never forget them, space cadets.