I have a few that I just have off the wall for a few things and I memorize those. Some I just use ssh keys. Others go off a pattern and I put hints in a file to figure it out. The account itself is not even put in this file, so I have to just know what the hints mean for both the account and what password pattern hints go with them. Usually, the user IDs are something I store in this file, because those get too tough for the aforementioned methods of determinism.