PHP Advent 2011: Cross-Origin Ajax with CORS

I've had the honor of writing for this year's PHP Advent, blessing you all about Cross-Origin Requests with CORS:

There's no doubt that Ajax is one of the most exciting, useful, and necessary web technologies available to front-end developers. Unfortunately, it's also one of the most restrictive — especially when it comes to gathering content from other domains. Web developers are nothing if not persistent, so we've come up with a variety of ways to get around cross-origin restrictions, including JSONP, server-side proxies made with PHP, ProxyPass proxying, Flash transports, creative iFrame uses, and more. What many developers don't know is that there's a W3C specification called Cross-Origin Resource Sharing, or CORS, which provides a standard for cross-origin Ajax requests with minimal hassle.

That's my Christmas gift to you all!