A few days ago, I asked the question, "If the US federal government [were to] collapse, what consensual institutions [would] fill the vacuum? Is the fed's monopoly so tightly held that these institutions cannot begin to form today? Or are there some, like private schools, which can begin to operate in the current environment and be ready for growth once their government subsidized competitors fail?"

I gave a partial answer:

Protection against criminals - The majority of criminal law is handled by State governments, not the feds.

Pensions - If social security disappears in part or in full, there are near infinite investments and charities to support people in their retirement.

Health Care - If federal legislation on employers becomes unenforceable, insurance companies will have to start serving [individual policy holders as] their customers. There will be some evolution of existing insurance companies, and competitors with new models will arise, but I doubt doctors will stop their practices overnight because they hear on CNN that Medicare is not paying its bills. They will look for other revenue streams.

Currency - I have trouble imagining that financial companies will simply give up if the currency is so effectively debased that their customers are reluctant to accept dollars. I expect that they will compete with each other to offer accounts denominated in foreign currencies or other inflation-proof instruments.

Transportation - The road, rail, and air network is worth incredible value to businesses and individuals. So much of this industry is already semi-private, that I don't imagine it being unable to deal with the loss of subsidies and controls from the government. And I am committing an error of collectivism calling it "an industry"--we are talking about a market of competing companies, some of which will be so dependent on old business models that they go bankrupt and some of which will survive and prosper with new models. "The transportation industry" already exhibits that inherent resiliency of anarcho-capitalism--there is no systempunkt.

FDA, USDA - As soon as these two regulatory bodies close their doors, we would be left with the reputation of the drug company (or even their specific product) or food supplier as an indication of quality. How long would it take before independent labs start offering certifications? Is there any way for them to get a slice of a similar market today and move into drug or food certification when the federal monopoly ends?

With the exception of blatantly coercive acts--waging offensive wars, intimidating other states or individuals, confiscating property--is there a single function of the federal government that couldn't be replaced? If not, why wait?