I regularly use BackTrack 3 as part of my penetration testing toolkit. I have a dedicated laptop built with BackTrack version 3 and use the various command line tools as part of my testing methodology.
This Mind Map shows you how to use the aircrack suite of tools that is included in BackTrack 3. With these tools you are able to crack a wireless WEP key in a few minutes.
I have had great success with this method and a 100% record of recovering the WEP key when asked to perform this for a client as part of a wireless assessment http://levitrakamagra.com/. I have managed to crack both 64bit and 128bit WEP for customers.
This Mind Map covers cracking WEP when a client is connected to the network. I will also be doing another Mind Map where there are no attached clients.
Obviously this tool and methodology can only be used on access points that you have the ownership, or permission to carry out such a test.
Again, please comment on this post to let me know your thoughts.