For large applications I use Dojo, for quick small apps and web pages I use jQuery. I focus my time on these two because I feel that they represent the best in their respective classes. But yes, I use Dojo, CSS and HTML that is pretty much it. For the back end I use Java, mainly because there is a wealth of middle-ware technology available for Java. I use JAX-RS to provide all of my services as RESTFull services.
http://www.ibm.com/social/impact/