The trick is that you have to POSSESS it, lest the digital house of cards block your access to your I-don't-know-where-it-is assets. Then you have to be able to find someone who actually wants it when things get tough.
Tangible properties, like real estate, are a better choice: you know where it is, it's marked, and it can't be stolen (someone might keep you from it, but that's a different problem).
The problem there is that you don't actually "own" real estate, you are just buying a certain degree of control over the property. If the government decides to change the degree of control individuals are allowed to exercise, you are just as screwed as a gold owner in the 30's.
But real estate cannot be used to barter for goods and services, especially in small quantities. Now take a silver dime and you might get a loaf of bread or a silver quarter and buy a gallon of milk.