About this question
What is the easiest way for two people – neither of whom are computer specialists and cannot meet in person – to send a password for an encrypted file that is attached to an email?
The two simplest methods are these: telephone the other person and read the password over the phone; or write in the email questions that the NSA and other hackers couldn’t possibly answer. The answers or parts thereof when compiled can then be the password or hashed to provide a password.
Asking non-technically minded people to install full PGP to send a password is not realistic. Is there a simple piece of JavaScript out there that can do a Diffie-Hellman, so the resulting shared key can become the password?