Flickr Link Preview - Greasemonkey Script

In my research into this goal, I discovered two reasons why my goal is unattainable using pure javascript:

1) Due to very reasonable security restrictions on AJAX calls, a script running on any page not hosted at flickr.com cannot communicate with Flickr via an XMLHttpRequest.
2) Even if I could get around #1, I would have to include my personal Flickr API key and secret in plain text in the javascript file. This is not only a bad idea, but against Flickr's Terms of Service.

The result is that the script must use a cross-site scripting technique to send information to a PHP program running on a server I host, which sends the request to Flickr and returns the remaining part of the script that knows what to do with the information from Flickr.

Get it at userscripts.org/scripts/show/39390.

Script website here.