I saw a site recently where a sample page format was
sitting to the right of a list of format names. As I moved
my mouse down the list of names, the sample format in
the page-box changed to demonstrate what that page
style would look like. I never clicked, just hovered over
links that altered a picture on the page according to what
link I was hovering over. I didn't view source and now
I can't find that site.
What was that? How did they do that?