Look up AIRSNORT and from there you can find more and more tools.
If you don't use range expanders, you can try turning off the SSID broadcast. Also, a simple MAC FILTERING helps immensely.
If your equipment supports it, move to WPA now.
-> http://www.wi-fiplanet.com/tutorials/article.php/2148721
discusses this so there's no need for me to repeat this usual.
Bob
Hi. The wireless network at work uses a 64-bit WEP encryption scheme. I'm wonder how easy it'd be for someone to intercept plain-text passwords sent through such a network. For example, what is the risk that my connection to AIM, which requires a password but probably doesn't hide it, can be obtained by someone else? How much is the regular internet traffic encrypted? Thanks.

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