In an ideal world, you don't.
There are various password hacks available some better than others.As several people have already said you need to be specific about your needs, is it a Windows logon password, something for a password protected document, or a logon password for a web site? for that matter is it even your password or are you trying to do something a bit naughty :-) ?
You're supposed to store passwords in your head. If you can't remember / remember which file you put 'em in (try searching your machine for files named "passwords"), it's tough I'm afraid. L
The whole point of passwords is they are not stored (generally) -- to prevent people who aren't meant to have them from having them. A system where you can just look up the password willy-nilly is not a very secure system.
Well it depends. Is it the login passwords? Web browsers' stored passwords? etc. Please Specify.