I just read through ParticleTree.com’s write up on The Hows and Whys of Degradable Ajax. The article describes a method of adding AJAX functionality incrementally in order to offer a complete backwards compatible application. The example application demonstrates this nicely (best to use Firefox with the Web Developers toolbar so that you can easily disable JavaScript while you test it – just remember to refresh after re-enabling/disabling it)
* This post was originally published on October 4, 2005 at http://www.csb7.com/blogs/whyblogwhy/2005/10/04/the_hows_and_whys_of_degradable_ajax