Here's a demo (Click HERE) of how a UK television show drove around and found a wireless network they could hack into using a wireless laptop and some free software available off the internet. This technique is called "War Driving".

Boy, was he surprised when they showed him his recently booked vacation plan! As you watch this, think about the information your business could be offering up to hackers if you are using the weaker form of wireless encryption called WEP. Everyone should be using at least WPA encryption.

Lesson Learned.