WiFi Recovery just analyzes the wpa_supplicant file on your device. It gives you the information in a convenient format that allows you to copy the password directly to the clipboard. In addition to copying the key, you can also export all of the information to a text document.
WiFi Key Recovery is a very useful tool that will allow you to reconnect to any known WiFi network without having to ask for the password and manually enter it again.
You need to root your device in order to be able to use WiFi Key Recovery.
Requires Android 1.6 or higher.