Web Sites Accessible for Everyone is a fairly comprehensive site, offering a variety of resources for anyone interested in website accessibility. I've found the AJAX and Accessibility section particularly interesting. Thank you University of Washington.
Tools for Web Developers. Yahoo gives away some free stuff for people who want to get into Ajax Development. This seems like a nice addition to the other libraries already available.
Ajax: A New Approach to Web Applications. From our own JJG, a look at the next big thing in web app interfaces. Link via some guy named Matt. Time to start studying XMLHttpRequest.