BP Simple Private is a Plugin that allows site admins to create fully private networks within their BuddyPress site.
Simple BuddyPress Privacy is a plugin that allows BuddyPress users to choose exactly who can see their profile page. They can choose display it to all (public), logged in members, friends only or just themselves.
LH Logged In Post Status is a WordPress plugin that adds a new post status of “Logged In” to the available status options in the Publish dialogue box. What this means is that posts can be published only to logged in users, which is an option that would enhance the privacy options available for post content.