They got a patent on geo-locating
http://www.digitalenvoy.net/news/pre...r_062904.shtml
"Patent number 6,757,740, titled, "Systems and Methods for Determining, Collecting, and Using Geographic Locations of Internet Users," covers the core methods used to determine the location of Internet users to the city level utilizing IP addresses. Furthermore, this patent claims a priority dating back to 1999 when the patent was first filed, and before any other current geo-location company was in existence."
1) Lookup surfer's IP
2) find match in a table with all ISPs & their IPs
The US patent office, again
