InSSIDer, a free application for Windows, scans networks within reach of your computer’s Wi-Fi antenna, tracks signal strength over time, and determines their security settings (including whether or not they’re password-protected).  Another application, NetStumbler, has long been a favorite for this sort of functionality, but it doesn’t work well with Vista or 64-bit XP.  InSSIDer, on the other hand, works like a charm on both Vista and XP, and it’s open-source to boot.

Give it a try!

Related articles by Zemanta

• Things To Know When Using a WiFi Hotspot Or a Public PC (makeuseof.com)