Project-open
Van PropellorWiki
]project-open[ is the open source alternative for huge and expensive enterprise project management tools. Just have quick look at what they offer on their website and you will see that they have features you can dream about and then some... Especially since they integrate with the open source scheduling tool Ganttproject. You can also have a look at the community driven dotProject as an alternative tool.
Check out their website for download and features http://project-open.org/
