With Browser Fairy you can have individual default web browsers for every app and every web page.
Stylesheet Download Tests
This page tests “whether today’s browsers will download stylesheets that are referenced with media queries that would not apply on that browser or device.”
Thee appears to be a lot of download overhead with media queries using link elements.
How I Use VMWare Fusion and Snapshots
Jonathan's cross-browser testing is pretty slick and answers a couple of questions I've had when thinking about the ideal setup. I think I'll follow this model myself, once I get some time to pull it all together.
Html5 cross browser polyfills – Modernizr
A collection of "all the shims, fallbacks, and polyfills [needed] in order to implant html5 functionality in browsers that don't natively support them."
20 Things I Learned About Browsers and the Web
“20 Things I Learned About Browsers and the Web” is a short guide for anyone who’s curious about the basics of browsers and the web." The illustrations are great and the implementation (using the canvas tag) is slick.