Sudoku

I was told this game drives people crazy ... and it is now my turn to be addicted !
Sudoku is a logical game whose rule is extremelly simple. A sudoku grid is 9 by 9 cells and each cell must contain a number between 1 and 9. The only rule is :

each line, column and 3x3 square must contain all numbers from 1 to 9each line, column and 3x3 square must contain all numbers from 1 to 9

Here is an example :
sudoku

you can play get a new grid everyday at http://sudoku.koalog.com

Have fun !