Useful websites (collection by Labnol) on the Internet to increase productivity and help learn new skills. These useful websites solve at least one problem really well. And they all have cool URLs that are easy to memorize thus saving you a trip to Google: https://www.labnol.org/internet/101-useful-websites/18078/.
Read MoreWiki
OpenProject is a web-based project management system for location-independent team collaboration. This open source application is released under the GNU General Public License Version 3 and is continuously developed by an active open source community: www.openproject.org.
Read MoreTrac is an enhanced wiki and issue tracking system for software development projects. Trac uses a minimalistic approach to web-based software project management: http://trac.edgewall.org.
Read MoreMediaWiki is a free software wiki package written in PHP: http://www.mediawiki.org/wiki/MediaWiki.