I’m working with a teacher that would like to take his students online for a short time.   Quick.  And there’s a rule in place that he cannot expose his students’ e-mails to public scrutiny, presumably because the IT folks in his area don’t want students to be left open to strangers contacting them.  I’ll argue that point another day. 
    Most tools require a student have an e-mail to create an account for a blog.  But not all.  And those that do also don’t necessarily expose that e-mail to the world.  If you were me, what would you recommend?
    Seems like Blogger‘s an option, as is Elgg.  So, too, is Moodle.  For that matter, what tools actually display an e-mail right up front?  Or don’t require one at all?  (I know Elgg’s a candidate here, too.)  Does WordPress MU require all users to have an e-mail address, or can the administrator set folks up without?
    Your suggestions?