DocBook is an XML vocabulary which enables you to create document content in a presentation-neutral form that captures the logical structure of the content. Using the DocBook Project XSL stylesheets, you can publish DocBook content as HTML pages and PDF files and other formats, including man pages, HTML Help, and JavaHelp.
Syntext Serna is a highly customizable, multi-platform, pure XSL-driven WYSIWYG XML content editor. It looks and works like a conventional word processor, yet it gives you much more flexibility to alter or reuse content while keeping its integrity intact. It lets you collaborate on compound documents that contain embedded data from various sources. Content is viewed as an integrated whole that is intuitively transparent to authors.
BIE (Business Integration Engine) is an open source integration system that makes it easy for organizations to exchange data with external trading partners regardless of their native applications. It competes in the same space as applications like Microsoft BizTalk except that it is truly cross-platform since it written in Java.
RefDB is a reference database and bibliography tool for SGML, XML, and LaTeX documents. Command-line tools allow interactive or scriptable access to the data which are stored in a SQL database. RefDB can also be accessed through a Web interface, a SRU interface, or via editor extensions (Emacs/vim). Libraries for Perl and PHP are available for programmers. RefDB provides sophisticated character encoding handling, using Unicode by default.
Staroffice/Openoffice to HTML Converter converts a Staroffice/Openoffice.org document to HTML, using xsltproc for the XML conversion and ImageMagick's convert to convert images. It creates a table of contents with links, and handles tables, styles, spans, and many other XML elements from a writer file.