Possible to restrict who sees calendar events?

[Jabong82]

Is there away to create a calendar that will only display say events posted by people users are friends/contacts with (ie change permissions etc)?

My forum can't really use a default calendar that shows everyone's business to everyone (I allow users to post events).

I mean I guess you could create different calendars, but that seems complicated and I think people won't want to sift through multiple calendars.

Any help would be appreciated. Thank you.