Gizmodo: GPS enabled Cell Phone released - locate your buddies!
Grope: Helio Drift GPS Buddy Stalker Vs. Dodgeball - Gizmodo

Basically, you can use the phone to find friends on you buddy list, with a few conditions. They have to have a Drift phone, too. They have to be on your buddy list. They need to have pinged the server with their most recent location. Still, very cool.
Now, thinking tangentially for a minute: what if the map was a concept map? You could discover who was in the same conceptual thought space at the moment, and go and join them in SecondLife or similar.

December 8th, 2006 at 5:04 pm
Do you know where i could get my GPS service by cell phones?
my friends download GPS software to cell phones, and their phone become the navigation system. so cool! but, how i can get
one too?!
December 16th, 2006 at 7:40 pm
Hi Joaquin,
I don’t know! I imagine that it’ll be mid-2007 before you can purchase one. But, thanks for the question