Perfectly Centered via CSS

One thing that has always been a struggle is how to perfectly center an object (for example, a DIV) both horizontally and vertically on a page. 

The other night I was searching for a better way to do this via CSS instead of using nested tables.  I came across Dead Centre, a website that demonstrates exactly how to accomplish this.  You can see some of the detail on the webpage itself, but also take a look at the source for more details on how this was executed.

This provided a truly dynamic design that was 100% CSS-based and works across all browsers.