Pour mener des projets à bien en équipe, voici quelques projets open source autres que Basecamp et CentralDesktop (qui eux sont payants, et pas à moitié) :

activecollab  : activeCollab is an easy to use, web based, open source collaboration and project management tool. Set up an environment where you, your team and your clients can collaborate on active projects using a set of simple, functional tools. 100% free  !

dotproject : dotProject is a volunteer supported Project Management application. There is no “company” behind this project, it is managed, maintained, developed and supported by a volunteer group and by the users themselves. The software is free to anyone who would like to download it. Day to day support is provided free by volunteers.

coghead : Coghead is using the power of the web to revolutionize application development. By making the development process faster and simpler, Coghead is empowering non-programmers, and IT professionals alike, to construct their own rich interactive business applications. And, because its 100% web-based, there’s never any hardware to buy or software to install and maintain.

A noter que Coghead n’est pas encore ouvert, mais semble totalement dans la mouvance Web 2.0 au niveau ergonomie. Il faut que je teste les autres.