You mean some item showing you exact location of other players, or exact location of any encounters?
I know nice feature in one small MMO where you can ask in guild for someones location. The location is correct, but not so accurate and is scoped to region. I would love to see such thing here. Go to radar station and ask nicely for someones location and you will get quadrant or city name to look. It would be another thing to spend some caps on.