cytomembrane hyperinvolution peart calathos
This page generates a random password using the method suggested by this xkcd comic. My word list is 173059 words long. That means there are 1730594 possible 4-word combinations. That's 896,967,607,451,228,385,361. If you cracked 1 billion per second, it would take 28.4 thousand years to try them all. I don't store them, but they are transmitted to you in the clear. If you're feeling particularly paranoid, you can run the Python code yourself on your own word list:
from random import SystemRandom
with open('/usr/share/dict/words', 'r') as wordfile:
wordlist = [word.strip() for word in wordfile.readlines()]
print choice(wordlist), choice(wordlist), choice(wordlist), choice(wordlist)