Finally, a "pure CSS3" demo that isn't a total gimmick. We'd be in good shape if there were as many of these as there are CSS3 icons and the like. Nice job.
And to anyone who wants to do this, make sure you have "overflow: visible;" on the container. The far left shadows in the demo get cut off because he set the overflow to hidden.
Very nice. One small nitpick - pseudo elements should be selected using ::, not : in CSS3