John

THE password cracker, understands many ciphertext formats, like several DES variants, MD5 and blowfish. It can also be used to extract AFS and Windows NT passwords. It has been written by "Solar Designer".


 * http://www.openwall.com/john/

There is a free version, a Pay-for Pro version, and a distributed version (like in Distributed Computing, share the work among many computers)

SecurityFocus Interview with the author

there is also rbjohn and pljohn

john