I just read about this a few minutes ago, so forgive me if this is old news, but it looks like Aptana has launched Jaxer. In their own words, this is:

Modern web sites and applications use Ajax to create engaging user experiences: the HTML and CSS are set in motion using JavaScript running in the browser and calling back the server. To achieve this, the server needs to prepare the web page appropriately, and to know what to do when the JavaScript calls it. But the server knows nothing about the HTML and CSS DOM, nor how to handle JavaScript data, and you can't code it in JavaScript...

...Jaxer changes all that. Jaxer is the world's first true Ajax server. HTML, JavaScript, and CSS are native to Jaxer, as are XMLHttpRequests, JSON, DOM scripting, etc. And as a server it offers access to databases, files, and networking, as well as logging, process management, scalability, security, integration APIs, and extensibility.

It seems rather interesting, and reminds me a of Dot Net with it's runat code snippets. What I find most interesting is that it even has support for Database connections. Like Adobe's AIR product, it extends the basic features of JavaScript to let you do things that you would normally do within a server side programming language like ColdFusion.

I'll be downloading this today and giving a fuller report later on, but folks may want to check it out. The price is nice too - free. I'm surprised they don't mention that on the home page or the FAQ, but if you go to the download page you see it mentioned there.