"a tool for checking foreground and background color combinations of all DOM elements and determining if they provide sufficient contrast when viewed by someone having color deficits. All the tests are based on the algorithms suggested by the World Wide Web Consortium (W3C)."

"This article will provide some techniques and general approaches to AJAX and dynamic content accessibility for rich internet applications. This article will not present everything you need to know, but will provide a general overview of making dynamic and complex scripted content accessible."

"I recently gave an internal presentation at Headscape about WCAG 2. A number of people expressed an interest in seeing it so I made a point to record it."

good summary of how the beeb considered accessibility for their new JS-heavy homepage

browser and os detection script