If you hook up your firewall and look at your logs after a voice chat or a file transfer or anything of the type you'll note that the IP of the other person is indeed logged. I don't know that there's really a way to prevent that, I suppose there'd be a way to mask it, send the wrong IP, but other than that I really don't know.

And the rest of it, I have no clue. Sounds like he either found a cheap trick and exploited it or has mad, mad skills. Either way it'd probably be best to stay on his good side.

And follow the other's adivice and install a firewall. You can get a good one for free from Zone Labs http://www.zonelabs.com/store/conten...sp?lid=pdb_za1

Unless you really are just trying to con somebody into telling you how to do it. In which case, good luck. 'cause I doubt anybody would even if they knew how.