I\'m writing a simple photo album app using ASP.NET Ajax.
The app uses async Ajax calls to pre-load the next photo in the album, without changing the URL in the browser.
If you are using Rails, then definitely try Wiselinks https://github.com/igor-alexandrov/wiselinks. It is a a Swiss Army knife for browser state management. Here are some details: http://igor-alexandrov.github.io/blog/2013/07/11/the-way-to-wiselinks-1-dot-0/.