TinyAJAX (PHP)
From the site (http://www.metz.se/tinyajax/index.php):
TinyAjax allows you to:
AJAX enable your pages without having to write a single line of javascript Call PHP functions in classes or as separate functions, you can even extend TinyAjax by subclassing it Let your PHP-code set which elements to alter and with what using behaviours Integrate it with a template system (smarty-example included) Easily have gmail style “Loading” notification when AJAX-code is executing Use PHP-functions for both AJAX callback and regular code