This FWA awarded site for French agency ultranoir is one of the most completely realised HTML5 sites I’ve seen yet. I particularly love the simplicity of their ‘about us’ section, which uses some nice animations to jazz up some clean graphics and type. 

The site works really nicely in a browser but clearly has touch devices in mind with nice horizontal dragging to scroll content areas. 

All in all a very impressive site and one I’ll probably cite as reference for future projects more than once.