DWR – AJAX framework for Java. Easy to use.
XFire – New SOAP framework for Java. Fast and simple.
ServiceMix – Enterprise Service Bus. Works well with XFire, Spring, and uses Drools for smart routing.
BIRT – Jasper-like reporting tool for Eclipse. While Jasper still rules, BIRT is starting to look good. Includes J2EE report output runtime as well.
That's all for now.