Take the Mensa challenge! These extraordinarily entertaining puzzles can confound even those with high IQs-and that's what makes them such delightfully tricky fun. A few can be solved relatively quickly, but the hardest may seem nearly impossible to crack. Give your skills a real workout on numerical conundrums, word games, lateral thinking problems, and riddles. Brainteasers, arranged in order of difficulty, train the mind and provide a good time...