Sudoku, anyone?

Sudoku, all the rage worldwide but still unknown to most of my friends and students here. At first when I tell them about it, they deny that it is of Japanese origin, even despite it's undeniably Japanese name!

I do not know why it has not caught on in Japan as much as it has caught on in the West...a matter of marketing? After a British newspaper published it, American newspapers were quick to follow...spurring a kind of sudoku mania across the globe. Funny thing is, it has not gotten back to Japan yet.

Have you played it yet? I like it but at the same time, it drives me nuts! All columns and rows and 9-square boxes must have the numbers 1-9 (but not more than one of each).