Depending on where the developed world heads, equities, commodities and property, or government bonds could be the investment.
There are three scenarios for the developed world (remember the BRIC and Indonesia etc still are dependent on the developed world to drive their economies). It can
— grow out of its debt burden,
— inflate the debt away, or
— fall back into recession, marked by the occasional default.
Each of those outcomes leads to a different portfolio.
Renewed growth would favour equities, but at the moment, this looks too hard to achieve. An attempt to inflate would be good for commodities and property but would be disastrous for government bonds. Selected equities might do well: those that can pass on the cost rises to customers. Those bonds would do best if the developed world goes into a recession.
Hope this explains the extreme volatility of markets.