Well, Citibank Japan doesn't charge for ATM's if one has over 1 million yen on their account, but charge about 2000yen of monthly management fee if one does not have at least a monthly average of 500,000yen on their account. That means that if you don't notice for a few years that you had a bit less than 500,000yen, you could lose everything little by little. And the interest in yen is of course the same as in Japanese banks.