If you enjoy sudoku puzzles, or are looking to buy a gift for someone who does, The Toughest Sudoku Puzzle Book is a wise choice. These puzzles are categorized into three sections: Tough, Tougher, and Tear-Your-Hair-Out.
These categories can sound fairly intimidating, but they are doable with patience and logic. With two puzzles to each page, the squares give you plenty of space to jot your answers, as well as whitespace outside the puzzle box to figure things out.
I received a complimentary copy from the publisher.