Book excerpt: Containing standard puzzles and killer puzzles, this new sudoku collection also introduces jigsaw sudoku. This puzzle is exactly the same as a normal Sudoku - fill in the rows and columns and boxes with 1 to 9 without the same number appearing in any row, column or box. BUT, in a jigsaw, the boxes are rather strange shapes. You can still use the same strategies but you may also find you invent some new ones.