HTML5 & CSS3 Readiness - Site submitted for the HTML5 Design GalleryScreen shot by J Kyrnin - courtesy HTML5 Readiness
This is a really great site to bookmark. It uses caniuse.com as the source for browser information, and it doesn't include mobile browsers, but for the desktop browsers it's really helpful. I also love that we can see support dating back to 2008. If you don't bookmark this page because of the inspiration, bookmark it because of the utility.
Have you built an HTML5 site? Or do you know of one that does a great job with HTML5? Submit HTML5 site designs to be featured on this site.