on November 8, 2005
First attempt of AJAX implementation within Joomla! was successful. See it live at http://www.jgp.net/index.php?option=com_contact&Itemid=3.
It was a fairly simple example which uses a Joomla! wrapper, wrapping a sample Yahoo! maps page.
Note 2014-01-15:
Since this site has been migrated, the link is not working anymore, but here is a screenshot of the demo.