Quote Originally Posted by John Imbong
Since the recommendation of CSS2 back in 1998, the use of tables has slowly faded into the background and into the history books. Because of this, CSS layouts have since then been synonymous with coding elegance.

Out of all the CSS concepts designers have ever used, an award probably needs to be given to the use of Negative Margins as being the most least talked about method of positioning. It’s like an online taboo—everyone’s doing it, yet no one wants to talk about it...
Original Article: http://www.smashingmagazine.com/2009...ative-margins/

Awesome article on the uses of negative margins. Definitely worth a read if you're an XHTML zealot like me.