Features of Online Sudoku More advanced features than you can shake a stick at

Online Sudoku is easier to use yet more powerful than 95% of computer-based sudoku games out there. It's surprisingly full-featured. The following is a list of just a handful of the cool features it sports:

• Beautiful, Easy-to-Use Interface We promise, you've never seen an interface this simple and easy-to-use for a computer-based sudoku game—much less an online game.
• Keyboard Shortcuts Never before has playing sudoku on a computer been so easy! Dozens of powerful keyboard shortcuts make it almost as intuitive as playing with pen and paper—an in a web-browser, no less.
• Powerful Marks System A problem with most computer sudoku games is that their marks are too darned hard to use easily. Online Sudoku makes it easier than you ever thought possible.
• Hundreds of Puzzles With hundreds of puzzles to play in four difficulty levels, you'll never run out.
• Input Custom Puzzles Want to play a real-world puzzle in the application? No problem—with the built in custom mode, it couldn't be easier to enter a puzzle you've seen elsewhere and be playing it within seconds!
• Save Your Progress Automatically save your progress across multiple sessions. A sophisticated auto-save ensures that you'll never lose your progress again.
• Play on a Plane or in a Car Because this game is web-based, you'd think you wouldn't be able to take it with you on a long trip. Wrong. Online Sudoku features a powerful offline mode that can queue up to 20 puzzles for playing when you're in the air or on the road.
• Play it Anywhere Because Online Sudoku is web-based, you can fire it up on any computer that has access to the internet.
• Share Puzzles With Friends You can easily generate links for your friends to your puzzle with all of your current progress, or to the a blank version of the puzzle you're working on. See who can solve the puzzle the fastest!
• Hall of Fame Registered users have the chance of showing up on the top scores list, letting everyone else know just how awesome they are at sudoku.
• Multiple Display Sizes Pick from three different display sizes to make the grid the size that's right for you.
• Undo/Redo Multiple Levels Hit the 'u' key to undo, the 'r' key to redo. Online Sudoku lets you undo/redo to your heart's content.
• Sophisticated Hint Feature Never again will you get stuck on a hard puzzle. Online Sudoku's sophisticated hint feature can help out with almost any puzzle and—what's better—it'll let you know the logic behind the hint it's giving you.
• Automatic Time Penalties In order to make the Hall of Fame times fair, if you use a time-saving feature your solve-time will be adjusted accordingly.
• It's FREE Most computer-based sudoku games worth their salt want you to pony up money to download and play. Online Sudoku is 100% free—and has more features than a lot of the other computer-based sudoku games combined!