A few days ago I was asked to find out where or close to where a user of ours was coming from. so i created this GEO location script Where does this IP Address come from
When ever a ISP buys a block of IP address they are entered in to a database. When a client of the ISP requests a new IP address the ISP gives them one from the block of IP address they they bought. With your IP address and the addressing information from your ISP I can look up the address of your ISP’s local router to get a general idea of where you are coming from (with in a few blocks in populated areas)
This information can be useful when generating ads for people from specific locations. For example: I would want to show a red state something different the a blue state in a election year.
Try it out and tell me how close I got Where does this IP Address come from