A man writes the same number, and nothing else, on 20 sheets of paper. Why? To figure this out--and hundreds of other mind-bending lateral puzzles, too--you'll have to really fire up your brain and imagination. At first, it may not seem as if there's enough information to come up with a solution. But look more closely; there's always more than meets the eye. Check your assumptions, ask good questions, retune your mind, separate the facts from the...