BuddyPress.org

Here’s something much less robust than what Jeff is creating. This one lets users control privacy settings of their profile information, and admins have no overriding control. Sort of like Facebook does, and privacy settings appear when someone signs up, plus when they edit their profile data. You might have to adjust or add CSS to work with your particular theme. Works with the latest version of BP:

http://simplercomputing.net/2010/03/18/simple-buddypress-profile-privacy/