I am also very interested in email-less login, or at least a site that is much more anonymous than the currently OACS provides out of the box. I would love to see a parameter in the the kernel (or maybe acs-subsite) that allowed you to toggle between real names and screen names. This would impact a lot of different packages, so it wouldn't be a trivial change. I've also thought of putting together a package that would allow users to send notes, kind of like emails, back and forth to each other through the context of the site itself. That way, the site could protect the privacy of the users by not giving out emails & real names at all, but still allowing communication.
I'm actually in the beginning stages of developing a site that requires this sort of approach, so I'm willing to throw my hat in to help with the grunt work.
