Recent Users, Users Online, Recent Albums, Leaderboard to only display your friends

hi, as per subject line, i am trying to create a facebook like social site where you can't see posts, photos, who's online, recent albums etc etc from members on the site apart from those that are your friends.

I don't want a user seeing a recent album from a total strange from another part of the world.
So it would be nice if there was the privacy option to only show all these modules populated with members that are your friends.

Does that make sense?

Thank you