Here is some old idea, but made only with pure CSS.
At first there was a variant with extra wrapper and two extra pseudo-elements on it, but then I rethought the code and made it all just on a single element by using radial gradients.
While this method is simple, there are some limitations: the background must be solid (however, if you’d try
background-attachment: fixed…), there are some positioning issues, but in other ways this method is rather bulletproof. And if you’d replace the CSS-gradients with simple images, this method could work in IE (maybe with some extra small fixes, I didn’t check).
Update: Lea Verou updated this experiment using the
background-attachment: local. Read about it in her post.
Published on April 21, 2012 in Experiments.