Dick Oz It's a marvelous WiFi monitor that can monitor all traffic 'in the air'. Even some encrytion protocols are supported, so one could run test using WEP and still monitor it. They have other packages, this is the one that monitors WiFi traffic if your WiFi adapter is supported.
It's very expensive for the casual user. So I'd only be interested in something like $50 (in stead of euro 400). Quite a challenge?