B. Mann Consulting

The web developer's list I'm on had an interesting thread this morning about detecting where people are geographically when they come to your website.

First, there is Networldmap, where you can visit and let them know what city you are coming from to help them update their database.

But, it all seems to be run by GeoBytes, which is commercial. They do have some cool free services, although their advanced stuff requires you to register. The fact that it is Javascript-only is kind of annoying -- I'd love to be able to call it in PHP scripts. I'm sure there are some more free location-based databases, but I haven't had the need to search for them yet.