Taskwarrior is a command-line TODO list manager. It is flexible, fast,
efficient, unobtrusive, does its job then gets out of your way.
Taskwarrior scales to fit your workflow. Use it as a simple app that captures
tasks, shows you the list, and removes tasks from that list. Leverage its
capabilities though, and it becomes a sophisticated data query tool that can
help you stay organized, and get through your work.