Non-cash economies would be my answer. Find business models that don't rely on consumers having access to money, unless you are providing necessities. Say said it best: when there's not enough cash available to satisfy desires, people find ways around it. If you can arrange to be that way, you can still profit.
As for investments, pick your index, close your eyes to the ups and downs and pray someone in government realizes that when people are willing to give you a negative real interest rate you should take their money and do something productive with it.
>Say said it best: when there's not enough cash available to satisfy desires, people find ways around it. If you can arrange to be that way, you can still profit.
The only way I'm able to interpret this as practical advice is "invest in the mafia". Unless you're talking about building up your personal skills - which, while good advice (if you can do something other people want then you'll never go hungry, no matter how bad the economy), doesn't really scale.
As for investments, pick your index, close your eyes to the ups and downs and pray someone in government realizes that when people are willing to give you a negative real interest rate you should take their money and do something productive with it.