Description: Su Doku, "the crosswords without words," come with a warning: it is seriously addictive. One doesn't need to be a mathematical genius to solve these puzzles; it is simply a question of logic and a little patience. Here is a collection of 100 new puzzles arranged according to difficulty.
Brief description: Wayne Gould is the brains behind Su Doku. A former High Court judge in Hong Kong, he now spends his time developing the puzzle.