I get paid in JPY but do most of my finance-related stuff with US based institutions so all of that is in USD. A move from 80 to 120 means a 33% pay cut all else being equal.

Though having said that as gnaget points out the USDJPY is inversely correlated to US markets. So all this time the yen was depreciating it was against a backdrop of strengthening markets. Meaning that if hedged properly the currency loss could be made whole through the stock market.

Also, a weaker yen means less income to report to the IRS and consequently less taxes to pay (from the perspective of someone like me who files taxes in the US).

So: stronger yen = higher income but lower return on investments + more to pay in taxes. (Though at the same time you have more USD to purchase cheaper stocks.)

weaker yen = lower income but higher return on investments and less taxes.