John the Ripper is a command-line fast password cracker, currently
available for many flavors of Unix, Windows, DOS, BeOS, and OpenVMS.
Its primary purpose is to detect weak Unix passwords. Besides several
crypt(3) password hash types most commonly found on various Unix
flavors, supported out of the box are Kerberos AFS and Windows
NT/2000/XP/2003 LM hashes, plus several more with contributed patches.
