casino-confidential.jpgToday's book is Casino Confidential: A Pit Boss's Guide To Beating The House. Let's stick with the gambling theme and play a little roulette. I've selected one number on the wheel. First person to randomly guess it wins the book. (One guess per person.)

For another way to win books and mental_floss t-shirts, send us a picture of you and our magazine. Email it to (more details here).

Update: Black 24! The winner is KerriH. I'll be in touch about your book. Thanks for playing! Get us your pics-with-the-mag for more chances to win.