A passive way to protect yourself is to buy commodities like gold, silver and oil. Gold in particular is considered a great hedge against inflation. If JPY begins to inflate, its exchange rate against other currencies will rise and gold prices (as measured in JPY) will increase. You will "profit" in the sense that you can sell your gold to repurchase yen after the inflation stops.<p>FYI, investing the GLD ETF is the best practical way to buy gold:<p><a href="http://finance.yahoo.com/q?s=gld" rel="nofollow">http://finance.yahoo.com/q?s=gld</a>