Don't forget Scriptaculous!
Built on top of the Prototype library, Scriptaculous (http://script.aculo.us/) provides a number of animation effects and ajax powered auto-completion form fields.
Dead useful, and a great time saver!
In the Introduction to Developing Web Applications with Ajax article we discussed the procedure used to create an Ajax application. As a developer, you probably noticed that the client JSP included a lot of JavaScript. Prototype is a JavaScript library for developing dynamic web applications, which aims to replace much of the …