The Life Changing Magic of Tidying Up - Marie Kondo
Ok, so maybe I'm a bit of a neat freak, but this book is more than just about teaching you how to tidy up. It's a way to learn valuable life lessons about letting go; how to reflect on your life and understand how others and even things have served a purpose (and can now be let go). Think of it more as, "Zen and the Art of Tidying Up." A short read.