If you too spent the holiday season conducting essential research in the field of pies, puddings, and chocolate-based desserts, then you'll know how Team Dewey feels. Some of us sought slightly more exotic fare by traveling across oceans to nations known for their cricketing prowess, their singing soap actresses, and their love of Rolf Harris. Which is how we know that only three kinds of books were published in the UK this year: those by TV chefs; those with mildly offensive four-letter words in their titles; and those containing hundreds of 9x9 grids sprinkled with digits and variously labeled "easy," "medium," and "hard." As far as we can tell, these three groups of works are currently mutually exclusive, but (if he's looking for new ideas) it's difficult to see how Jamie Oliver could fail with an expensively-packaged retrospective of terrible sudoku puzzles from the '90s. Meanwhile, the popularization of variations on the sudoku theme continues apace: the Guardian has begun publishing a daily kakuro puzzle (also called "cross sums" in the US since the '60s), and the first kakuro books have begun to appear. As the Guardian puts it, "[d]espite the use of numbers and the need, at first, for basic addition and subtraction, [kakuro] is really a test of logic, not of arithmetic," and so we would class works on kakuro as we do works on sudoku -- at 793.73 Puzzles and puzzle games, not 793.74 Mathematical games and recreations.