Quick link - pseudo elements in CSS
I wrote this post a while back. The content can still be relevant but the information I've linked to may not be available.
Enhance your website text with pseudo element CSS selectors. Jonathan Snook has written a short article about pseudo elements that explains all.
I have used the :first-letter pseudo element on a few occasions. It's great for adding drop-caps to paragraphs and cross browser support is pretty good.
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