RogerZF

I want to be able to find how close my users are to eachother. I have a HUGE list (thousands) of IP addresses in a MySQL database. I can match IP's with longitudes/latitudes. My problem is finding other users close to the current logged in user. Do I need to match longitude/latitude for EVERY IP and calculate distance? Wouldn't that KILL the server AND the SQL server? What's the most efficient way of doing this? I know Myspace has a "find users close to you" feature, but I can't figure out how they made theirs. Also, I don't think zip code is much of an option as not every country has a zip code. I have TONS of international visitors (USA, Europe, Australia, Canada, UAE, etc.). Do all those countries have zip codes? I can't think of an efficient way of doing this without killing the server.