There was a time, though it's hard to recall, before SuDoku took over the world. Now, you may have a new game to play. Enter KenKen, a new game that has gained enough ground that is now featured in The New York Times, right next to the venerable crossword.Invented by Japanese math teacher Tetsuya Miyamoto, the puzzle requires you to fill in numbers that do not repeat in a line or column, just like SuDoku, but numbers within each box must also perform a specific mathematical function (an example: the box labeled 10x needs to contain two numbers that, when multiplied, equal 10. I'm no genius, but I'm guessing you'll want a 5 and a 2 in there. The numbers in this one go from 1 to 6, because it is 6 by 6. Get it?). Miyamoto believes in what he calls "the art of teaching without teaching;" he gives his students trial and error puzzles and activities and allows them to learn for themselves. KenKen sprang out of this philosophy. I've never really gotten the whole SuDoku thing, but on trying this one briefly this morning, it seems like I could spend an afternoon procrastinating with this. You can use the one attached to this post, it's the medium difficulty inaugural Times puzzle.Here is the KenKen website. If little math puzzles aren't your thing and you're looking for a real time-wasting brain teaser and have an iPhone, I cannot recommend Frenzic enough (for you non-iPhone users, there is a desktop version, but it isn't nearly as good). It's sort of like Tetris, but way more fun. I am currently ranked 61st in the world, so, see if you can take me on.