Valuable assets

From Organic Design wiki

The state of the financial system is a real concern with the very real possibility of a total economic collapse looming. Many people are afraid to keep their money in any currency because the collapse of the USD or EUR could very easily cause a chain reaction causing all the currencies to fail. Most of these people turn to precious metals, especially gold and silver.

When it comes to gold and silver, I think silver is by far the best option for many reason that are better explained by the Silver Shield Report. But this article is about what other kinds of valuable assets could you convert your monopoly money into while people still believe it's worth something?