A very enlightening article from oreillynet:

http://www.oreillynet.com/pub/a/wire...wardriver.html
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Armed with an old Dell laptop with an Orinoco Gold wireless network card, I took off. I also had Lucent's Range Extender antenna that plugged into the card, and propped that up on the dash, giving the laptop a much better signal than it could have gotten from the card's built-in antenna. Also included was my Garmin eTrex GPSR attached to the serial port of my laptop.

Be sure to set your network adapter's profile for "ANY" network name, and you can also vary the scanning speed of your network adapter under Options, Scan Speed. The only downside to scanning quicker is that it tends to consume batteries a bit faster, and causes the network adapter to heat up somewhat since it has to work harder.

Programs like NetStumbler are passive, meaning all they do is listen for networks. Doing so does not violate any FCC regulations, but when you start interacting with networks, the law gets somewhat cloudy. As a professional, I did not want to invade anyone's network. A personal firewall was installed on my laptop, not to protect me, but to protect others by keeping me off their network.

Since I live in a very rural area, I was not expecting to find any access points until I reached more populated areas. Imagine my surprise when less than 5 miles from my house, the first access point I find is from a small church out in the middle of nowhere!

It wasn’t long into my trip to Charlotte before access points started popping up on my screen quicker than I could count. I found access points coming from industrial centers along the interstate's service road, along with convenience stores and other shops. Even while crossing high overpasses a few new ones would pop up…
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