use OpenOffice/LibreOffice to create troff man pages
xslet project provides some XSL libraries and applets.
Multi-format web publishing system based on Texinfo
A JavaDoc doclet that outputs source code structure in XML format.
Make a tag cloud from text in your files
To retrieve obscure syntax of languages, or bookmark code comments.
Objective-c code Apple style documentation set generator
DITA Open Toolkit plugin that creates an HTML QA error report
Text Viewer that displays text similar to pango
Capture and save screenshots like never before.
MS Word / HTML to CHM / Web Help converter
Create executable Java archives for HTML content.
Technical Documents
A methodology for documenting CSS and generating styleguides
An intelligent screen capture application
Woas is a complete wiki in a single HTML file, forked from stickwiki.
Handbook Sources for Plasma Active