Yahoo! knows! where! you! are!

Yahoo's punter-locating database officially launched yesterday and already has privacy advocates in a flap, despite offering users complete control as well as expecting them to lie every now and then.

Fire Eagle is a free central service to which punters can subscribe and maintain their current location. Services then subscribe to it in order to become location-optimised - so one updates Fire Eagle to say one is in the Highlands and any site that integrates with the service can pick up that information to deliver Highland-specific information.

The granularity of information supplied to services is under control of the user, so I might provide Fire Eagle with my SatNav coordinates, but only want my current postcode passed on. I can also refuse to provide detailed information, switch off the service when I want some privacy, or even lie about where I am - Yahoo makes great play of providing a service, not spying on anyone.

Punters will also be sent a reminder every 45 days to confirm they still want to share their location, and Yahoo! say they'll delete all historical data immediately - though they can't make the same promise about services using the data.

More than 50 such services are already signed up to use Fire Eagle, with applications such as Nokia-owned Plazes offering to upload punters' GPS coordinates automatically, so all your contacts can see where you are all the time - at least until you tell the service to stop snitching on you.

Yahoo! has gone out of its way to allay privacy concerns, and isn't betting the farm on the success of Fire Eagle - none of Yahoo's own applications will be using the service until it proves popular, as Yahoo co-founder Dabid Filo told the BBC:

"If we get millions of consumers using the service and have thousands of applications, we think it will be good for Yahoo. We want our services to be location aware as well and obviously the more consumers that are willing to use it the more we will be able to tailor our services to them and the better it is for us."

The problem comes when and if such services become ubiquitous, when the authorities start demanding historical information (as they already do from the mobile-network operators) and when opting out of the service prompts the question "what have you got to hide?" ®