Are you in the US? Do you have a Kindle? If so then please support us and help us to continue to run sudoku.org.uk as a free site.
We have just released a number of titles for the Kindle. These are active content which means that you can play Sudoku on your Kindle with optional auto possibles and full access to pencil marks. We think it is really great and looks fantastic on the Kindle. Please take a look.
Need help with your Puzzle solving
In addition to our solvers we also offer utilities to help you solve various puzzles. One example is out Killer/Kakuro possible value calculator.