Former pick-up artist (PUA) and PUA coach Mark Manson offers some counter-intuitive approaches to living a good life in The Subtle Art of Not Giving a F*ck. The book is well-written, funny and full of wisdom.
It's not a book about not caring about anything, as the title might imply. But rather it's about whittling down what you care about so that you can focus on the most important things, and are not drawn into wasting time/effort on the things that aren't important.
But there isn't much that is groundbreaking. Many of the principles he espouses are ones I have already adopted. (Not that I've adopted them well, but this book does not help one with that; it only serves to convince the reader that they are good principles to espouse.)
Nevertheless, I read most of it anyway because the anecdotes the author shares as interesting/illustrative/entertaining and the writing is well done.
If you're looking for some life principles, The Subtle Art of Not Giving a F*ck is a reasonable place to start.