Postnuke
Postnuke is a free, open source content management system forked from PHP-Nuke, released under the GNU General Public License. The Postnuke project was started because some PHP-Nuke users believed that there should be a more open development environment than PHP-Nuke had at the time. They felt that the only way this could be done was to develop their own fork of the PHP-Nuke project. Postnuke is now a separate project from PHP-Nuke, sharing very little code (if any) with the original project.Some other projects have forked from the Postnuke code themselves. Two notable examples are Envolution and Xaraya.
