... and even if you choose (intentionally or otherwise) to expose your email address to the world, moodle employs a mechanism which hopefully should make it harder for spammers to harvest email addresses from SCoPE user profiles. I don't know how effective this mechanism is in practice, but have a look at the source of the user profile page - the email address is obscured. For example, my email address in the source of the user profile page looks like this:
przemyslaw@stencel.inf
(just a short note from a lurker from the other side of the world. BTW, I greatly enjoy reading SCoPE discussions and learn heaps from them - big thanks to all of you :-) If only I could participate more often..., but you know, it's a time management issue :-))