When I open the finder menu, I noticed under "shared" my kids computers and one called "tahasf-willist" It is listed as a PC and I can't connect to it. I kick it off by turning wifi off, but soon after (5-15 minutes later) it's back on. I have no idea who it is, and there is only one PC in the house on the wireless. I have a wireless password and but I also have 3 daughters that are doing god knows what on the internet half the time. How can I find out who/what that is?