. These tabs record usage in browser history so the "back button" behaves as a user would expect (the jQuery plugin for this is "history_remote").
Jquery from John Resig and the jquery team
. I use jQuery because it is packaged with the CMS I use (Drupal). I wrote a module to only include the plugin and associated css on specified pages.
Their website is Drupal too, jquery and dojo playing together!
Its development is driven heavily by the Ruby on Rails framework, but it can be used in any environment.
The Yahoo! User Interface (YUI)
and I will add it.
You can see the results of this poll here