The Book of Awesome by Neil Pasricha
Pick this book up, open it to any page, and remind yourself that the world is indeed full of awesome things, even when some days we find it very hard to see it that way. This is a good tool if you're looking to train your brain to have a more optimistic habits, if you're into the whole gratitude thing (yes, there is neuroscience behind that btw!), or if you just need a mental pick-me-up and some good, old-fashioned perspective and a laugh once in a while. By the person who runs the 1000awesomethings.com blog, in case you need yet more things to smile about in various formats on all your devices.