eXist-db is a feature rich Open Source native XML database
Multi facets CASE/AGL for easy project developments
console tools, batch scripts, shell scripts, shell tools, utilities
CAM XML Editor for XML+JSON+Hibernate+SQL Open-XDX sponsored by Oracle
DocBook Publishing Made Easy
XML Application Framework based on JAVA
XGAP is a PHP web application generator
Information Manager(split/analyze/compare/combine).
xslet project provides some XSL libraries and applets.
DocBook Editing and Processing for Eclipse
Framework for search and display of heterogenous document collections.
Cookbook Style Document for DocBook Customizations
A GUI frontend to Apache FOP