[d0de]

>This turns your email inbox into a giant password manager

I already use my primary email for this purpose. Most passwords I memorize, but some, for services with requirements so arcane that memorization isn't possible, I just email to myself with a unique key I remember. To get the password, I just search my email for the key.

Yes, this makes me vulnerable if my email is ever compromised. But my primary email is already a single point of failure and pretending otherwise doesn't do me any favors.

I could use a password manager, which would have the advantage of encryption. But it's also limited to those places I have access to it. I can store the database in my dropbox, but that limits the platforms I can access it from (at least, without some serious headaches) and makes the whole process that much more painful.

[forensic]

It might be worth pointing out that most password managers also use email for authentication.