Manos Batsis, one of my colleagues, has written an article at xml.com. The article’s title is Sarissa to the Rescue and it’s about Sarissa an OSS Javascript library, developed by Manos. Sarissa is a cross-browser library that wraps XMLHTTP (XMLHttpRequest on Mozilla) and various other XML APIs.
Now that Javascript and asynchronous web user interfaces are beginning to be more and more important in web application development I think that Sarissa might be a good solution for more portable Javascript code.
BTW did you know that Javascript has a unit testing framework (ECMAUnit) and a lint program (jslint).