Nir Sofer - 137KB (Freeware)
WirelessNetView is a small and lightweight utility, which runs in the background of your system and monitors the activity of any wireless networks within your range.
WirelessNetView provides information on: SSID, Last Signal Quality, Average Signal Quality, Detection Counter, Authentication Algorithm, Cipher Algorithm, MAC Address, RSSI, Channel Frequency and Channel Number.
System requirements: Wireless network adapter and wireless card driver that works with the built-in wireless support of Windows XP/Vista/7/2008. Operating System: Windows 8, Windows 7, Windows Vista, Windows Server 2008, or Windows XP with SP2/SP3.