Aircrack-ng - Aircrack-ng is an 802.
Vistumbler - Vistumbler is a wireless network scanner for Windows Vista and Windows 7. Features:
netsniff-ng - netsniff-ng is a free, performant Linux networking toolkit.
inSSIDer - inSSIDer Essential makes it easy to maintain small business WiFi.
WirelessKeyView - Recover lost WEP/WPA keys stored by Wireless service of Windows
Homedale - With Homedale you can search for Wi-Fi / WLAN Access Points and monitor their signal strength.