Sajax is an open source tool to make programming websites using the Ajax framework — also known as XMLHTTPRequest or remote scripting — as easy as possible. Sajax makes it easy to call PHP, Perl or Python functions from your webpages via JavaScript without performing a browser refresh. The toolkit does 99% of the work for you so you have no excuse to not use it.
CPAINT (Cross-Platform Asynchronous INterface Toolkit) is a true AJAX (Asynchronous JavaScript XML) and JSRS (JavaScript Remote Scripting) implementation that supports both PHP and ASP/VBscript.