Hi tha_watcha, is it possible to add this as a feature request. It would be very simple to implement:
In user control panel, add three check box:
1. Block other users from sending me PM
2. Block other users from sending me Email.
3. Block other users from sending me friend request.
In backend DB, just add one more column in users table called "BlockContact"
It can have values "pm,email,friend" for each user.
If it has all three values, it means users does not want to receive pm, email and friend request.
If it has values "pm, email", it means user does not want to receive pm and email only. He is fine with others sending him friend request.
If it is NULL, then they are no blocks.
All this assumes that pm, email and friend request are enabled in Admin settings.