Seeking a Browser Compatibility Reference?

Fr05t asks: "Gone are the days of being able to use the W3C specs for DHTML and Javascript as a solid reference for every browser. To make things worse I've been finding more and more I'm required to build richer web content that runs on all browsers. I've found many books that have a chapter on Browser Compatibility, but is there such a thing as a complete guide to the incompatibilities between IE, Netscape, and Opera? I'd even settle for a site dedicated to the documentation of the browser SNAFU."