It’s a well-known fact (at least in the candy blogosphere) that Japan has all sorts of crazy Kit Kat flavors. I’ve reviewed some here and here, and Jen’s got a whole blog devoted to it.
Via my friend Katie and Jezebel, here’s a map of this year’s regional flavors. If only it was blow-upable or more legible!
Varsha 
sophia cook 
Vishal