Get a whole heap of passwords from random.org. Create a text file with the sites you use with the usernames/passwords. PGP Encrypt the whole ensamble with a good strong password. The only one you really need to remember.
Forget your password? Once you reset via email, as soon as you get access to that encrypted file, get a new random password and reset it again. Save the new password in the encrypted file.
Password managers often connect to the internet to retrieve your passwords so if you lose your access, you're SOL. I also wouldn't trust a browser plugin as that may be prone to compromise. Backup to your laptop or something if you need to take it with you, but keep it encrypted until needed.
Forget the password to the encrypted text file? Throw your life away and start a new identity.
Edit:
Pointed out below (and I agree whole-heartedly) use /dev/u(a)random
Forget your password? Once you reset via email, as soon as you get access to that encrypted file, get a new random password and reset it again. Save the new password in the encrypted file.
Password managers often connect to the internet to retrieve your passwords so if you lose your access, you're SOL. I also wouldn't trust a browser plugin as that may be prone to compromise. Backup to your laptop or something if you need to take it with you, but keep it encrypted until needed.
Forget the password to the encrypted text file? Throw your life away and start a new identity.
Edit: Pointed out below (and I agree whole-heartedly) use /dev/u(a)random
And idupree's points are spot on.