Well,me am no Sudoku enthusiast,but a friend is and he has send me this info which I think may be useful for Sudoku fans here....
« Simple Sudoku »
A Sudoku puzzle maker and solver for Win9x, Win2000 & WinXP
Simple Sudoku makes high quality puzzles that are symmetrical, have a single solution, and do not require trial & error to solve. The user can also choose between five levels of complexity - from Easy to Extreme. Each puzzle is generated randomly so there is an almost limitless selection.
Not only does Simple Sudoku make challenging puzzles, it also provides tools to help solve them - removing the drudgery but not the fun. Keeping track of possible values for blank cells (candidates), providing filters and color markers are just some of the tools available to make solving even those really tricky puzzles possible. Also, if you ever get really stuck, Simple Sudoku can get you started again with a discrete hint (without giving everything away).

Source & Download Link
There is also an Indian version made by an Indian techie
tech_cheetah wrote:hi Friends
I have developed 'Sudokool' , a cool pc version of the popular
game sudoku. I developed it as part of my Core Java Project.
I m giving a preview below
You can download the game from here
U need the jre 1.5.x to run game, although jre 1.4 will work ,but looks
will not be so cool.
Alternatively if u have JDK 1.4 or 1.5 then u don't need jre bcoz jre comes
included in JDK.
You can download jre 1.5 from here
Credit to tech_cheetah@digit forums


