Fragment identifier history in Safari! Now this is something that really excites me! If I understand this code correctly, something like this could be used on Ajax-driven pages to let clueless users use the back button when they want to see the previous "state" of a page. For example, if I load new content into DIV A, the user ordinarily has no way to see the previous content using the back button. But with this hack (which at the moment works only in Safari, and then only in certain circumstances), you could help to "idiot-proof" your site. (Never underestimate the number of idiots on the web!) This page has a simple demo and access to the source code.