Free Download: http://win7gadgets.com/pc-system/xirrus_wi-fi_monitor.html
Xirrus Wi-Fi Monitor is a simple Windows gadget that looks like a radar and shows all the available Wi-Fi networks and their relative range. It is a small toll that doesn’t take up that much space and can forever be turned on in your sidebar.

Click here to learn more about Xirrus’ wireless networking solutions