Emacs can do everything, it can even manage your todo list. Org-Mode is "for keeping notes, maintaining ToDo lists, doing project planning, and authoring with a fast and effective plain-text system."
I have seen demos of Org-Mode and was very impressed by it. It certainly has all the features needed for doing The Cycle, the system I recommend in Time Management for System Administrators
If you are in the Philadelphia area, tonight PLUG presents Paul Snyder speaking on Org-Mode. Check it out!