Encryption Buddy is an app for your Mac that will allow you to password protect and encrypt any type of file. Encryption Buddy has a clean, easy to use and understand interface: Simply drag-and-drop the files that you want to encrypt / password protect into the main window, supply a password, and click "Encrypt My Files!" Decryption is just as easy - and no one can decrypt your files unless they have the Encryption Buddy app and your password.
Updated on May 31 2018
Note: Now requires OS X 10.11 or later running on a 64-bit Intel processor