Just like anything else in life; you can take this knowledge and do good or evil with it. I’m sharing this because of three reasons. First, it requires a bit more than the average understanding of how to work with wireless networks. Second, having this sort of knowledge people will come to you for assistance. When they do these tools are VERY useful. And finally, mastering these tools will permit you to “harden” your wireless security, efficiently developing your technical skills to a higher degree.

How To Crack WEP and WPA Wireless Networks from Speedguide.net