How do I do awesome refreshless page changes like GitHub do?

They have a detailed blog entry up on how it works (HTML5 History API) here: https://github.com/blog/760-the-tree-slider

http://www.asual.com/jquery/address/ is a jquery plugin which supports HTML 5 History API in addition to the traditional hash tag method. This is useful for supporting the transitions in older browsers (via hash tag) while using the HTML 5 method when available.