MacWireless has created a free Dashboard widget that shows you the WiFi networks in your vicinity. AirPort Radar is a clean little widget that tells you the signal strength of the networks it finds, and tells you which networks are open. Handy for situations when you’re looking for free WiFi and would rather not flip through every network in your AirPort status button in order to find which of the listed networks is open.
As an aside, I’m not condoning going around looking for open networks for nefarious purposes. Some networks are open by choice, some are not. You can usually tell which ones are open by mistake, because they use the default names provided by the base station hardware. If the network is called “netgear,” “linksys,” “default,” or something similar, odds are the owner isn’t open by choice. I’ve seen networks with names like “GoAheadUseMe.” Then again, I’ve also seen networks with names like, “DontEvenTryIt.” Odds are someone with a name like that is already in a corner window, watching you with an 8x scope.
