Similar story. A friend and i were arguing about whether you could solve sudokus by brute force in reasonable time. So we whipped out a couple of laptops and tr

Similar story. A friend and i were arguing about whether you could solve sudokus by brute force in reasonable time. So we whipped out a couple of laptops and tried it. I had a brute force solver (kind of branch-and-bound-ish, ISTR) finished before he had his constraint-based approach running, and it solved any puzzle in the blink of an eye. To capture some of the fun of human Sudoku-solving, i think you'd want to have some sort of metric for how brute the force is, and then see if you can write a solver which is as unbrutal as possible. I'm not sure what that metric would be, though.