Horizontally Center Layout in CSS
http://www.christopherjason.com/articles/horizontally-center-layout-css/

Jason, Chris
ChrisJason.com
2005

Abstract:

A good way of dealing with users on different screen resolutions is to center your Web design horizontally. This will ensure, regardless of the user’s screen size, that there is an equal amount of space to the left and right of the main design area, producing an overall "fuller" look to your site.