Where I live, I can detect 6 other WiFi networks depending on where I stand in the house. All of them have wireless signals that extend into my house. Over the last few months I’ve had to change my base station channels because someone bought a new router with a new default channel and accidentally jammed my signal. When it got too much, I did the only thing I could and bought some powerful repeaters. I know for a fact that one individual who broadcasts his wireless SSID doesn’t even have a computer with WiFi.
My contention is that if you decide to use wireless then you should be aware of the technology and, in most cases, be prepared to share. I share my wireless. Why doesn’t everyone? Security? But once you get past your wireless encryption, you’re sending your data, unencrypted out into the general Internet.
Anything really important, like your banking details, is encrypted from the browser even in a wide open unencrypted wireless network.
Your email provider doesn’t provide you with SSL?
Call them now.