CSS Tricks is awesome. Chris Coyier is basically the CSS god, and his posts are always about the newest and most highly relevant topics.<p>Joel on Software is old, and not updated often, but still an unbelievable source of knowledge about programming and especially developer careers.<p>And of course shameless plug for my own blog, Hacking UI, which I do read it every day since I develop it. My partner and I write about front end development, Design and everything in between.