TeamBox
Open source and totally free ● plus a free online hosted service!
complete
● very simple and cool, but not totally obvious what are tasks and what are lists
● tasks have start as well as end date which allows Gannt charts ● gives a twitter-like stream of events
● no milestones—have to use tasklists (but function similarly) ● RoR code is a little harder to install
Could be very good for some situations