Tip of the day,
Wanna reproduce smartnavigation behaviour for your web pages?????
Was playing around with the feature provided by ASP.NET and it performs somewhat like this:

       function TrialSaving()
           return false;
       function tryMe()

   <iframe name='StorageSpace' width=100%></iframe>

Call function TrialSaving before submiting your form. And, voila, the page does not seem to refresh. U can go about adding hidden fields to indicate last focussed controls etc.  
Of course this is a miniature version, can be modified to perform better and add more functionality.