Sudoku fever has officially stormed the nation. These fiendishly popular number puzzles have a universal appeal - no maths ability is needed, it's just a satisfying logical puzzle. Once you've done one, you will be hooked. The Daily Mail is Britain's biggest-selling quality paper, with a circulation of around 2.2 million. Their Sudokus have drawn hundreds of thousands of fans, and these bumper books will be among the biggest yet with 150 puzzles each.