Bruce Schneier's 'Password Safe' has been made open source. One can download a .exe or Linux binary files. Can also compile it from source. (I haven't used it yet. I made my own years ago.)
Bruce Schneier is active in the security arena and has designed several algorithms that have been well received by the security community.
I use 'mkpasswd' on Linux to generate user IDs, passwords and answers to "forgot your password?" questions. All random and unrelated to all aspects of my life.
BTW, rainbow tables won't help with encrypted files. They provide some assistance with unsalted hashed passwords. And hashing a password does not encrypt the password.