It's been a week since I implemented the system David Allen outlines in Getting Things Done. It's been the most productive week I can remember, and I don't think that's just placebo effect. A central thesis of the book is that one does well to focus on "next actions" in one's projects. Whatever you want to do, figure out what the exact next actionable step in that project is. Then create an organizational structure supporting lists of those next actions. Do it properly, and you don't get stuck on projects, you don't neglect anything important, your file systems and calendar contain only what they ought to, and you are ready to spring into productive action in any situation where you might find yourself ready to work.
It's a simple but powerful idea. Allen focuses on the way in which it keeps your brain from doing something it's pretty bad at (remembering and retrieving all your projects and the tasks necessary for each) and frees it to do what it's good at (addressing a given task once you know what it is). I agree that much of Allen's system's value derives from that, but I wonder how much of the system's value comes simply from forcing you to spend more time thinking about what can be done, now, to concretely advance your plans. There are kinds of working-in-circles and self-deception that simply can't happen if you're following Allen's advice.
From the book's cover I wasn't expecting a work of philosophy, and while it's certainly not as incisive or intellectually nourishing as Epictetus's Encheiridion, it is a contribution to what we might call "applied philosophy of mind." Allen's craft is getting people to use their brains more effectively, and he is a thoughtful observer of human psychology (so, from the chapter on the long process of going through all your stuff to figure out what all your projects are: "Keep in mind that some potential anxiousness is going to surface as you make your stuff more conscious to you than it's been. Create whatever supports you need."). More often than I expected, discussions of paperclips and how to subdivide lists included quite general insights into cognitive functioning.
This isn't a motivational book in that it's dense with statements that are supposed to motivate you; it's a motivational book in that it's about how to improve your life given the nature of human motivation and cognition. On this subject I find myself returning to the David Foster Wallace's late work, especially The Pale King, which is also a book about what human psychology is like and how to live as well as possible given what is true about psychology. In some sense it's a fictional (and, yes, more profound) complement to Allen's book--both are about distraction and being able to focus completely on what's in the moment. Interestingly, Wallace's late work is also largely about the value of transcending boredom and (literally) finding value in whatever task is at hand, no matter how routine. The heroes of The Pale King would heartily approve of long attention spent on one's paperclips.
There's room for a course to be taught on the philosophy of the mundane. There's plenty of material in the ancient Greeks, though Wallace benefits greatly from being able to tailor his work to contemporary culture. There would be room in such a course for some notes on Getting Things Done: a book which, despite (and because of) its long discussions of, e.g., filing cabinets, has much to say not only on how to harness your cognition but what your cognition is like in the first place.