This is an oxymoron at a time when CD’s and govt bonds yield in the 5% range.
You will have to assume some risk to get that kind of return. I don’t think the example of your wine futures and conservative fall into the same category either.
If you want to be conservative, shoot for about 8% return
My suggestion: 1/3 cash (e.g. CD or Money Market), 1/3 US Stocks, the remaining third equally divided (~11% each) between 1. foreign stocks/currencies, 2. gold or oil, and 3.other commodities.
If you don’t want to be conservative or you are simply looking for suggestions for that last 1/3 of your portfolio, I would consider Chris’ recommendation a reasonable one.
Maybe it’s just that I am old-fashioned (though not that old) and wouldn’t put my entire nest egg into a single wine basket.