there are programs out there that allow you to gain access to peoples computers using their ip addresses, although the IP address is assigned every time you log onto the internet, for the duration you are on the IP address stays the same. I suspect the guy had said program to access your computer, as it has been said, it's easy to find out an IP address, once you have that it's easy to get into someone's computer if you know what you are doing. One of the guys in my class managed to gain access to the NASA file servers, and the CCTV system, he also managed to do it at Glasgow Uni.