How close can you identify a user using asp.net and webservices

Question

The task is simple, and the answers might be many. But here goes: On my website I'll make an InfoAboutYou.aspx page. So far i got the IP and the browser name and version, but ill like to expand, with just about every thing i can look up about the curret user/ip and hes Browser/OS Does it exists any free webservices that kan lookup more information about a specific IP?

The idea is to see how specific a random user can be pin pointet

Thank you

Answer 1

You can use various service to determine a geographic location.

One example is:-

http://www.ipgeo.com/

Answer 2

There are plenty of things that you can determine by using JavaScript and having it post back to the server like some of the stats that Google Analytics does. You can determine screen size, etc.