A simple password generator that works on *nix, and generates passwords out of real words.

pass.py

#!/usr/bin/env python

# author: Brandon W Maister
# This file is in the public domain

"""Create passwords using random words

Long passwords are better than short, a long (20+ char) password made of
whole words is better than a short one, unless the attacker knows that you're
using whole words.

This is good enough for me.
"""

import sys
try:
    from random import SystemRandom
    random = SystemRandom()
except ImportError:
    print 'weak random numbers'
    import random

def makepass(min_len=20):
    with open('/usr/share/dict/words') as fh:
        words = fh.readlines()

    password = ''
    while len(password) < min_len:
        password += random.choice(words).lower().strip() + ' '

    return password.strip()

if __name__ == '__main__':
    if len(sys.argv) > 1:
        try:
            print makepass(int(sys.argv[1]))
        except ValueError:
            print "Only argument is the minimum length for the password"
    else:
        print makepass()