BaseX is a light-weight, high-performance, and scalable XML database system and XPath/XQuery processor, including full support for the W3C Update and Full Text extensions. An interactive and user-friendly GUI frontend gives you great insight into large XML data instances. It is platform independent and works out of the box.
betterFORM is an implementation of the W3C XForms 1.1 Recommendation. It allows easy creation of highly dynamic Web 2.0 user interfaces with attractive controls and layout. You can add validations, calculations, actions, and events to build complete Web applications in a declarative way.
Java XML XPath - Eclipse Templates is a set of 24 Java editor templates for easily working with XML documents in Eclipse. It lets you just type XML in any Java editor and select what you want to do with the XML document. It uses the DOM parser provided with the JDK, so there is nothing more to install. Instructions, templates, and examples for using XPath are included along with three cheat sheets for working with the DOM and XPath.