Project Mgt

eGroupware
Trac
RT
Redmine (Ruby on Rails)
TaskJuggler

Endeavour
web2project

Collabtive
PHProjekt

SO Planning
project-open
DotProject

Stand-alone

GanttProject
OpenProj
TaskJuggler

Discussion

http://www.junauza.com/2010/04/open-source-project-management-software.html