I want to expand on these resources to create a good post about wifi pentestint on Raspberry Pi. I will also include Wifite which has made the process really easy for me.

http://www.catonrug.net/2014/05/prepare-reaver-for-raspberry-pi.html

http://lifehacker.com/5873407/how-to-crack-a-wi-fi-networks-wpa-password-with-reaver

http://askubuntu.com/questions/362146/how-to-install-cowpatty