There and Back Again

AJAX library for Java generates JavaScript from Java classes. Proxy classes are used in JavaScript to call Servlet methods on the Java Tomcat server. Provides lots of examples to help you get started including a Multi-User chat example. Looks to support automatic fallback to iframes if XMLHttpRequest is not supported. Also has easy hooks for providing a global loading status.

Supports: ASP, Cold Fusion, Io, Lua, PHP, Perl, Python and Ruby, asynchronous operation only. Provides Cross Browser XMLHttpRequest based AJAX support, provides a procedural JS api. Works by registering functions to export on the serverside which generates javascript to put into your HTML pages. The functions are exported with a x_ prefix, functions then work like normal javascript except the last paramater is a callback function for the result.

A PHP AJAX lib providing mapped functions and asynchronous operation. Mapped funtions are procedural and are prefixed in javascrpt with xajax_. The unique feature is that you don't write callback methods in your JavaScript code, instead you create an xajax response object that says what elements to do content replacement with or even what JavaScript code to add to the page.