4) Man's Search for Meaning By Viktor Frankl: Frankl talks about his time in a Nazi concentration camp and what he learned from the experience. Where the rest of us may see only horror and death, Frankl was taught about life, meaning, and death. It's a truly profound book that can change not just how you view the rest of your life, but how you'll deal with your eventual death.
5) Mere Christianity by C.S. Lewis: Even though the book bogs down in the final third when Lewis gets into theology, this still may be the single best book on Christianity that I've ever read. If you know a Christian who wants to get deeper into his faith, he couldn't do much better than this book.
6) Gates of Fire: An Epic Novel of the Battle of Thermopylae by Steven Pressfield: If you're not into non-fiction, here's the best piece of historical fiction you're ever going to run across. It emphasizes sacrifice, honor, valor, and courage while telling the story of one of the greatest battles in human history: The Spartan stand against the Persians at Thermopylae.
7) Atlas Shrugged by Ayn Rand: According to a poll of conservative bloggers only the Bible had a bigger impact on their thinking than Atlas Shrugged. That confirms my own experience, because along with the Rush Limbaugh show, nothing pushed me towards conservatism more than reading Atlas Shrugged. The only caveat? It's 1200 pages; so, it's not a light read.
8) Winning Through Intimidation By Robert Ringer: This book would more aptly be titled "How To Avoid Being Intimidated," but that wouldn't be as catchy. The theme of the book is that people are often manipulated and intimidated in subtle ways. Once you identify what's happening, you'll get a much better understanding of how the world works and how to make your own life easier to manage.
9) Awaken the Giant Within: How to Take Immediate Control of Your Mental, Emotional, Physical and Financial Destiny! By Anthony Robbins: Yeah, yeah, I know. "Anthony Robbins? Isn't that the infomercial guy? The one with the big teeth? Come on, John!" Look, Robbins can teach you how to manage your emotions, your goals, and your life like no one else on earth. That's why, other than the Bible, there's no book I would more highly recommend than this one.
10) Basic Economics By Thomas Sowell: There are two problems that prevent most people from truly understanding economics. #1) It's not intuitive. You'll never get a proper handle on economics just by using common sense; you need some expert instruction as well. The problem with getting that instruction is #2) Economics tends to be boring. In Thomas Sowell, you have a master instructor who can explain the subject matter in a way that makes sense without putting you to sleep. If you could only read one book on economics, I'd say it should be this one.