I like web front-end using Java script, AJAX more than Flash/Flex. Although RIA technology is improved , I still love to direct code in HTML, CSS, and Java script. They allow me control the basic foundation stuff, so I can avoid lock-in framework.
I start to use GWT (Google Web Toolkit) from 1.5 and it helps me quick demo UI layout and idea. I like to write a road map to explain how I learn.
Manning- GWT in action
Prentice Hall- Google Web Toolkit application
Apress- Accelerated GWT, Building Enterprise Google Web Toolkit Applications
RESTFul and GWT