I've had to create some password scheme where certain chars change depending on the device, site, company, .... so I can remember more passwords. It gets a bit ridiculous when you support 20 odd clients with 300 odd users (windows and pop passwords) and servers between them + then having to remember all your own passwords for devices, web sites, game clients (seeing as most new games require you to authenticate with a server) as well :s
I don't have any of these passwords writen down but do carry around a piece of paper with R4000 odd worth of ADSL usernames and passwords for my clients.