My current work involves xybrix, an xml based GUI form builder (very cool) www.claroline.net an OnlineLearning tool
The idea of IncidentalCollaboration is a good one I believe to explain some of what happens in a complex OpenSource project like ArgoUML.
TouchGraph offers a very interesting GraphicalSolution? to reducing the complexity of the communications that pass between members of a team on a complex project.
ck out must see! http://www.touchgraph.com/TGGoogleBrowser.html
you can reach me at dddaniels at magic.fr