The new track a friend product from Google - Latitude may need some change in the attitude of people regarding privacy if it is going to become really successful.
Granted I have already had three requests to share my information today, this tool no doubt will be used for pinpointed advertising and may not prove popular with the general public.
The product is available for PCs, PDAs and smart phones. May have come in handy when I lost my last iPhone. I could have had it set for a friend to be able to triangulate where the phone was. But at this stage, you are required to type in where you are.
If they incorporate the tracking element the GPS programs offer in smart phones we could use Latitude to track lost phones... something to think about Google.