wlan-ui is a very small Linux GUI tool for connecting to wireless networks. It is written in perl, and is a basic example of using perl with Gtk and Glade.
wpa-buddy is a tool to decrypt WPA-PSK protected traffic. It can work in real-time (sniffing packets from a network interface) or in batch mode (reading packets from a capture file). It also produces nice output telling you what's going on.
Wvlan Monitor Applet
Wvlan Monitor Applet is a very small applet that shows you how far you are from the basestation if you are using wireless networking.
Xiwtool is a graphical Wireless Access Point scanning and configuration tool.
XNetworkStrength is a tool to visually track wireless connectivity between a laptop and a local access point (AP). It uses only the X11 windowing system for its graphics, and should compile on any Linux system.
xwconfig is a gtk based application for configuring wireless devices. It is based on and uses large chunks of iwconfig from the wireless tools package.