I use a simple system for which to remember and create passwords for various websites. First, I thought up a word for each letter of the alphabet. For example, the letter "s" might be "spiritual" or "somewhat".
Then, I take last letter of each site (before the .com/.org/.gov etc) and remember the word i thought up. Hubpages.com would be "s". so i type perhaps spiritual for the first part of my password.
I then count the number of letters between the two dots. www.hubpages.com would have 8 letters, so at the end of the word i add the number 3 times. In this example, it would be spiritual888.
Not sure if it's applicable to computer systems, but it's helps me on various websites.
Don't try to guess my password, because I didn't use this system for this site, nor on any other big sites like facebook or twitter... :-)