This map was taken using the following:

• HTC Desire Smartphone running Android 2.2
• Android Market ap 'wardrive' this uses your GPS and wireless conenction to pickup all signals in range and outputs a .kml file for a Google Maps API
• GPS Visualiser http://www.gpsvisualizer.com/map_input?form=google Input the kml file into this great application and you can output the data to suit.

RED = WPA security
YELLOW = WEP security
GREEN = Open network (should be a hotspot!)