Generate a set of random passphrases for you to choose from.
...The passphrase-generator defaults to only 3 words instead of the 4 suggested by XKCD, but uses a larger dictionary found in many unix like systems at /usr/share/dict/words. It also provides estimates for the entropy of the generated passphrases. The randomization is based on /dev/urandom and SHA1.
See http://xkcd.com/936/ for an entertaining take on passwords vs. passphrases.
See my post in stackoverflow for links to other solutions and discussions on passphrases vs passwords: http://stackoverflow.com/a/12646320/1148030
Perl Password Generator using LINUX /dev/urandom, randomized by time signature and hash final masking. Usage: /usr/bin/perl mkpw-hash-alpha.pl [--hash=MD5/SHA1/SHA256/SHA512] [--length=integer<17] [--cycles=integer=1...3]