Ok, I've pretty much deduced that it's impossible to get a div or any other element to extend to 100% of the page-height -- but I still want to. The only work around I've seen so far is to wrapping my div in another div with a repeating background.

That just seems like it defeats the entire purpose of CSS. I want to be able to quickly "re-theme" my site with CSS. I'd really rather not revert back to tables. Anyone have any suggestions? I just want my content visibly separated from my navigation.