Japan Rail Pass is a good deal for those who plan to travel on Shinkansen over long distances. For other people, not very much so. The local day passes, such as JR East's tokunai pass or the subway equivalent, are also difficult to realize true savings. Therefore, it is probably best if you pay as you go. You can, should you choose to accept the mission, purchase tickets at each station before you embark. Or you can pick up an e-wallet card like Suica or Pasmo. The Suica & N'EX is a good deal.

As for electronics, Akihabara. There are many "duty free" shops on both sides of Chuo-dori. They have salesmen who can help you bridge the voltage gap. If you or your companion know some basic electronics symbols, you can discern the markings yourself.

Ask for "menzei" on purchases over 10,000 yen. You can avoid paying the 5% consumption tax. The store clerk will fill out a form and staple it in your passport. Duty free shops should take care of the paperwork automatically for you. Some smaller shops may not have the forms on hand to process this for you.

Japanese mamas usually transport their larval offsprings in a mamachari, short for mama chariot, or single gear bicycle with baby seat.