The latest Japanese-inspired numeric logic game downloadable version, and perhaps most refined, is Sudoku Companion from Verek. A Macintosh app that will help you solve Sudoku puzzles or generate your own, ranging in difficulty from Easy to Fiendish to Insane. You can save your favorite puzzles and print them out, too. Also, for those of you with the new MacsIntel, you'll be happy to know that Sudoku Companion is a universal binary, so it will cruise right along on your newer hardware.