One thing that is really strange about Japanese culture, their very sophisticated and/or complicated loos! I remember my BF went to Japan (cos of work), and found that the offices like to outdo each other with loos with tons of functions! But a loo with an SD slot is another thing altogether!
Other then that, how about vending machines where you can buy your mem cards, comics! Wonder how long that would last outside of Japan. Re-stocking it would be just useless.