Recently I noticed that an ad banner displayed my hometown. I'm living in a very small town with less than 20.000 citizens. My dial-in node is not located there.

I tested this with Firefox 4, Opera 11 and Comodo Dragon 10 and it worked in all three browsers (with AdBlock switched off etc.). Geolocation is deactivated, browser history is switched off, third party cookies are not accepted.

If I locate my IP address with online tools, the location of my dial-in node is shown, not my hometown.

But how does it work then? Any ideas?