this is such a unique idea for a calendar..

apparently, the ink slowly absorbs into the calendar as the day goes by..

and then, the ink also reacts to heat, 

so as the months change, the color of the ink change too..

i want one!

(credits: http://www.oscar-diaz.net/)

ps, i got my KIN TWO recently. it's pretty nice..sometimes it's slightly laggy, but other than that, a-okay!