We're pleased to announce that a version of Seadragon Ajax is now available in source code as part of the ASP.Net Ajax Control Toolkit. This is distributed under Ms-PL, the open source compatible Microsoft Public License (http://www.opensource.org/licenses/ms...).
You can find the ASP.Net Ajax Control Toolkit here: http://www.asp.net/ajax/AjaxControlTo...
Because this is released under Ms-PL, you can do pretty much anything you want with it: host it on your own site, modify it in any way you choose, or re-distribute it with your own custom solution. If you come up with some great enhancements, you can also contribute back to the open source project on Codeplex.
Images, JavaScript, and Flash files that PHP sends to the browser are not affected by the GPL because they are data. However, Drupal's JavaScript, including the copy of jQuery that is included with Drupal, is itself under the GPL as well, so any Javascript that interacts with Drupal's JavaScript in the browser must also be under the GPL or a GPL compatible license.