Both my workplaces require computer passwords to change every 90 days. Each password must have capitals, lowercase, numbers, AND special characters. It was so difficult to come up with anything remotely memorable that would meet this criteria until it hit me- Scripture references! John 15:5, Luke 10:41, etc., suddenly it's easy to think of and easy to remember, even if I have to change it frequently. (And, as a bonus, helps me with Scripture memorization.)