Nestumbler

NetStumbler is licensed as freeware for PC or laptop with Windows 32 bit and 64 bit operating system. It is in connection category and is available to all software users as a free download. NetStumbler allows you to detect Wireless Local Area Networks (WLANs) using 802.11b, 802.11a and 802.11g. You can use it to verify that your network is set up the way you intended, find locations with Netstumbler is the best known Windows tool for finding open wireless access points ("wardriving"). They also distribute a WinCE version for PDAs and such named MiniStumbler.