`pet` is a simple command-line snippet manager. It allows you to write and store snippets for the command-line, so you don't need to remember all the commands you frequently use in you terminal. It can sync your snippets to the GitHub Gist, so you can always take your snippets with you.
Taskwarrior is an open-source, cross platform time and task management tool. It has a command-line interface rather than a graphical user interface.