Today, I attended this workshop @ webstock: http://estelle.github.com/CSS-Workshop
It was great. Great pace, great set of tips and tricks and as usual, great people and atmosphere.
Here some links that I found useful:
http://www.google.com/webfonts
http://leaverou.github.com/prefixfree/
http://lea.verou.me/css3patterns/
http://www.standardista.com/world-flags-with-css3-gradients/