If you use yahoo messenger you can play chess with someone in your group. Only people you approve can communicate with him.
DD8 hooked herself up and then showed DD6 how to do it. When they are at school I pull up their yahoo messenger just to make sure there isn't something shady going on.
So far, the only people on their list are the grandparents and an uncle, of course, DH and I.
I haven't seen any weird requests pop up from strangers, although I would guess that's a potential caveat.
It's pretty fun. We are lame in that I'll be on this forum(too much!) and my messenger icon will pop up. It's usually DD8 in her room asking me to play chess. So we play online with her upstairs, me downstairs even though we have a chess board in the living room.