Best Currency To Invest In 2010 Investing With A Weak Currency - Japanese YEN?

Investing with a weak currency - Japanese YEN? - best currency to invest in 2010

Hello,
I am an American living in Japan, with a salary of Japanese yen and the yen is at a historic low against the dollar at the moment, which raises many concerns. When I came 105/dollar in April 2005, the yen. Now he is 123/dollar, means the 17 to 19% of income is ... disappeared. (I did not convert transfer some of my money yet /.)

Of course, no one can answer the questions of whether the force or the yen, but I'm doing on the lookout for suggestions, what with my money. I read somewhere that the Japanese economy (despite the fact that stocks are at record levels now) is still worth investing, as in should be available (a saving of more bull) by the year 2010 approx.

As an American living in Japan, with a salary of Japanese yen, which is the best thing to do?
1) Please wait and do nothing and hope for the strengthening yen.
2) investing in Japanese equities
To invest 3) in America (or other) values
4) Other

Ideas?