The Airport Monitor Utility might do what you want...
http://www.macupdate.com/info.php/id/13809
http://www.trulycertifiable.com/products_airportmonitor.php
$10 shareware... Check the screenshots to see if it does what you are looking for...
Is there some way of keeping track, in real time or otherwise, of who is (or how many) accessing an open wifi connection? A friend of mine has a coffee shop in a fairly busy downtown area. He maintains a dsl connection that has wifi built into it. He was asking me if I knew a way of keeping count of how many users were on his wifi connection at any given time. Since we both use apple computers he thought that I might know how.
cheers
grim

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