Promotional giveaway poster from Bell Telephone, circa 1969
L. and I took our cell phones on our trip to Japan. Mistake. Japan has the World's most advanced cell phone technology; not only were our phones useless, they seemed prehistoric. It's not about games or cameras or computer access--Japan envisions the phone replacing a wallet, holding all information (memberships, identification, cash, credit) that can be accessed by a variety of sensors installed in stores, gas stations--even vending machines. After returning home, we referred to our phones as rocks. "Do you have/did you charge your rock?"
Currently, some 3G phones will work in Japan or one can rent a SIM card with a Japanese provider that enables one to use their own phone (international roaming rates apply).