XHConn

Web site: http://xkr.us/code/javascript/XHConn/

License: Creative Commons Attribution-ShareAlike

XHConn is an extremely lightweight wrapper that provides cross-browser XMLHttpRequest support. It's a good choice if you don't want to bother with cross-browser support but want to take care of the rest of the details yourself. The implementation is simple enough that you could easily make your version using the examples in Chapter 1, "What Is AJAX?"