Pass Generator does one thing, and one thing well. It generates random passwords. This little app sits up in the status bar of your Mac, and with a single click gives you access to a random password generator to your liking. You can configure the password length, and which characters to include in the password. This app also gives you a list of the previously generated passwords so you can copy them into your clipboard.
Pass Generator will not make you coffee in the morning or serenade you to sleep at night. It will only generate random passwords, and it does a fine job of that.
To setup Pass Generator to start on startup, edit your Login Items under System Preferences > Users & Groups > Your User.