Having a scaling full-browser width (and height) background seems to come up more and more. Wanted to post this article from over at CSS-Tricks that shows multiple ways to get this effect — some pure CSS, others with a jQuery bit mixed in:
The article is nearly two years old, but still completely relevant and functional.

RT @ryankeefer: RT @ryankeefer: Perfect Full Page Background Image http://t.co/qvxLSeSf