Detects Wireless Networks with InSSIDer

inSSIDer scans networks within reach of your computer's Wi-Fi antenna, tracks signal strength over time, and determines their security settings (included whether or not they're password-protected). inSSIDer works like a charm on both Vista and 64-bit XP and is open-source to boot. This tool is a must-have for hunting down Wi-Fi networks on the road.

is available as a freeware only for the Windows platform and requires .NET 2.0.