I thought the Sudoku craze might have peaked and subsided by now, but no. I was just combing through Vertical Inc‘s catalog when I saw this book, titled: Oekaki: Paint by Sudoku. It works exactly as it sounds—by solving Sudoku puzzles of varying degrees of difficulty, you end up drawing pictures of things like geisha girls and the Statue of Liberty. Sound like something you or your Sudoku-obsessed mother would want for her birthday? You can buy the book here.