I've always been one to keep an eye on politics and the economic climate of this country and to a lesser degree, other countries. If you are thinking of investing in foreign currency, you HAVE TO.
I think right now is a bad time to consider making any investments in any kind of currency (well, Yen doesn't send any red flags up for me) but with The Greece Situation trying to pull the Euro down and our own imminent threat of disaster, you might be better off to move out of America and use a different currency to invest in the dollar. We're no where close to being out of the woods with our own economy. Matter of fact, it's partly because of China getting sick of carrying our asses, which is why they are strengthening.
I have always thought buying land was the best bet. You can still get undeveloped land around here for as little as 350/acre. All you have to do with that is sit on it. Not to mention (oh, I'm a survivalist, by the way), you will have something to fall back on should the shit completely hit the fan.
Investing in other property is good too, but to me that takes way too much luck because you still have to count on the stock market to ensure that the house you just bought for 50K doesn't wind up being worth 15K tomorrow with you paying a loan for 75K. This happened to a lot of people when all those subprime mortgage bubbles burst a few years back.
Anyway, if you want to be truly conservative with your savings, the only solution is to physically buy things of value and sit on them. Putting your cash into the bank is no guarantee (the value of the dollar goes up and down) and investing in trade/stock/blahblahblah is risky on it's best day. I say options 1 and 2 are your best bet, with perhaps 10% devoted to options 3 and 4 on those days that you're feeling lucky.
Undeveloped land, metals and gems, guns and ammo...these are all good things to buy and hang onto. Wine and cars are fine, but they depend too much on a strong economy to move, I think.