Mkpass
Mkpass - Command line Secure Password Generator
mkpass is a simple command line utility to generate secure random passwords. You can easily redirect these to a clipboard or copy and paste as needed.
I use a password manager and generate random passwords every time I need one. And while most password managers include a generator, there are times I need one outside of that.
The code is written in java so it should run on any OS that supports it. Lastly, the idea and core code came from a Wikipedia article. I just took this and expanded...