Some entrepreneurs are already taking the principles of swapping—use everything and anything you already have to survive—to create another offshoot system, one that turns a hefty profit. Called the sharing economy, it is perhaps best exemplified by Airbnb, a service that enables people to rent out their apartments like hotels. Other sites let you turn your driveway into a parking space, your car into a taxi and your tools into a rental service. Forbes estimates revenue flowing through the U.S. sharing economy will hit $3.5 billion by the end of 2013, and maybe more. It’s worth mentioning that some business associations and government members are terrified of this rise: like most alternative economies, it’s largely tax-free.
“Economic theory has always got to be historically bounded,” Beggs says. “I think it’s a mistake to think you’ll find the workings of modern money by going back to the origins of money.” He does point out that, while barter may not have been widespread, it’s possible that it happened somewhere and led to money, just given how much is unknown about such a large period of time. 

The Internal Revenue Service (IRS) considers bartering a form of revenue and something that must be reported as taxable income. Under U.S. generally accepted accounting principles, or GAAP, businesses are expected to estimate the fair market value of their bartered goods or services. This is done by referring to past cash transactions of similar goods or services and using that historical revenue as a reportable value. When it is not possible to accurately calculate the value, most bartered goods are reported based on their carrying value.
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