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Dr. Karl's most recent book, Game of Knowns might make a nice Christmas pressie for someone in your family. Goes for $22-32 online and in most bookstores, $18 is the cheapest price I have seen anywhere. Plenty of stock at Logan Hyperdome (although I'm not sure a lot of books are read in this area :P).
QBD Has this for $22.99 with free shipping.