It's been tried before, but I think now is the time to promote JavaScript on the server side. It's a brilliant idea.

https://developer.mozilla.org/ServerJS

Advances in server-side development seems to be in a lull. The number of languages that a web developer has to work with has got to decrease if the difficulty of creating web applications is going to get significantly easier. The average web developer has to work with SQL, a server-side language, HTML, CSS and JavaScript. Between all these languages is an impedance mismatch that increases code size and complexity. With the growth of AJAX, the mismatch between the server-side language and client-side JavaScript continues to grow.

JavaScript is a pretty good language, and it's the most widely-used language. Yes, JavaScript came out of the oven a little soon, but its still a better-designed and more-powerful language than PHP. And JavaScript is posed to get better with the advent of EcmaScript Harmony. With server-side programming, developers don't have to wait for the browsers to update their JavaScript engines.