PSPassword is an application to encrypt and decrypt all types of files, so that they are not readable if the program itself and the password you have chosen are not used.
This was one of the contest entries for the Scenery Beta 2009 (PSP Applications).
Run the homebrew and follow the steps that appear on the screen to create password for the file that you would like to encrypt.
It does not have a graphical interface so you will need to know the location of the file that you want to encrypt, and enter the file path manually.
When you want to decrypt a file, you will have to open homebrew again.
Note from developer:
Please be warned that once you encrypted a file with PSPassword, you can only decrpyt it using the application.
If you forget the password you be unable to recover the original file, since the program, for security reasons, does not store the password anywhere.
Lack of a file explorer which forces you to know precisely the location of the file to be protected.
- SceneBeta - https://psp.scenebeta.com/noticia/pspassword