NetStumbler (Network Stumbler) is a tool for Windows that facilitates detection of Wireless LANs using the 802.11b, 802.11a and 802.11g WLAN standards.
License: Free
Kismet is a powerful and versatile tool ideal for advanced users needing comprehensive wireless network analysis and packet sniffing, primarily on Linux systems. In contrast, NetStumbler offers a simpler, user-friendly experience for basic network scanning on Windows, but lacks the advanced features and capabilities that Kismet provides.