Changing URL without Reloading in Browser

I have thought about changing the URL bar (location) in the browser without reloading so that the currently displayed dynamic page can be recreated later on without the user having to follow the same navigation path to get there. We already use this feature in Yahoo Map and Google Map. This also fits the REST model. I haven't had time to find how to do it (well, because the need has not actually appeared yet). Today this post provided the solution: location.hash. Then the URL becomes the URL that will reproduce the page rather than how we landed here.