Not all modules have been "groupalized" I think, but quite a few have (news, calendar, faq, content sections, display, etc.) To define a group, just go to /admin/ug and define them.
You can associate several modules to different groups or different group types according to the group type definition. The documentation is there but it is not specific enough IMHO. Maybe some examples would help.
Basically you have to define a group type, which can have several groups inside it and each group can have subgroups. For our site (fslc.usu.edu) we created a group type called "FSLC Projects" so that the different members of the projects our club is involved in, can have their own news, calendar, etc.
The groups pages are accessible at /groups, which should show all the public groups. I wish each group could have a user-defined "Group Homepage".
Janine, thanks for the pointers. They are very helpful. It's nice to see flurfy folks around here. I think flurfly will contribute a lot to OpenACS by providing commercial hosting using it.
