A tongue-in-cheek Sudoku Book Programmers Understand
Trust me, programmers will understand this
For someone you love who supports your habit
For the love of your life -- that supports your habit
Sudoku World Tour (sudoku history)
Keep calm meme sudoku style
Here's how it works. Give them the board with givens placed (see example below) and let them solve it. Then wipe the board clean with a cloth, napkin or paper towel and it’s ready for a new game. Play new games again and again.
For new games go to the main 4x4 page where there are 288 unique combinations of numbers, all valid 4x4 puzzles. Write some givens and let them solve it.
Links to more sudoku informationSudoku Techniques
Sudoku - the puzzle that addicts