Groups of Students in a Course

[mforbes]

What is the best way to structure a course so that students can work in groups on assignments? There is a brief discussion in the docs suggesting that students self-organize, but it would be really nice if there was some way of doing this that made it easy for instructors to visit each group for grading.

I was thinking about something like having a course with only "groups" as students instead individuals. This would work well from a grading standpoint, but then only one student will have their email associated with this. Is there some way of associating multiple emails for a single "student" in a course? (Manually modifying the .course file is fine in our case since we only have ~30 students.)

Another option would be to have all the students register for the course separately, but then designate one student from each group as the host: they would invite the other students to collaborate on their project. Is there some way of hiding the non-host students and/or collecting assignments only from the hosts?

Another option might be to have the students work in separate folders in the Shared class project (if #5507 is resolved) but this might create performance issues unless we can buy a sufficient Boost. Is it worth considering having ~10 groups with ~3 students each working simultaneously in an appropriately Boosted shared project?

Any other suggestions?