So what you want is that you have a site map structure and when you mouse over a link it runs off and gets a specific DIV from that page?
it should be possible to use ajax to retrieve the page html source and parse it for a specific div. large memory hog. would it be possible for you to add a bit of code to each page that would render just the div that you want as you could pass that as a parameter when calling the ajax function ie http://mysite/mystructure/mypage.php?showID=myID this way would be quicker as you would not be loading all the page content.
