It's hard to imagine now, but there could come a time when there's no such thing as a local currency or even a dollar bill itself.
That's far off into the future, but many people are already using digital currencies—a virtual peer-to-peer payment system that's held by individuals rather than a bank—to buy everything from electronics and jewelry to newspapers and basketball tickets.
Currently, bitcoin, the most widely used digital currency, has a present market value of $8 billion and about 80,000 transactions per day are made, according to PwC.
Bill Barhydt, a digital currency expert and president and CEO of mobile banking company Boom Financial, said that number will grow exponentially: He has seen market valuations as high as $1 trillion. Digital currency has the potential to disrupt everything from banks to payment companies, foreign exchange operations and more. "Just think of the cross-border implications," said Barhydt. "You can settle in real time on networks without banking or Forex requirements."
A number of innovative companies have developed ways to make it easier for people to use virtual money.
2014 CNBC Disruptor Coinbase (No. 35) is the largest bitcoin service in America. It's a digital wallet platform that allows merchants and consumers to send and receive bitcoin payments. It also offers businesses the tools they need to accept bitcoin as a form of payment.
Brian Armstrong, Coinbase's co-founder and CEO, calls bitcoin "money made for the Internet."
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Credit cards, checks and other payment systems were not built with the Internet in mind, he said, and "as a result, payment processing has been translated for the Web versus tailored specifically for it. The bitcoin network makes something possible that never was before, which is the removal of a third party to verify a transaction."
Currently, Coinbase has 32,000 merchant partners, including the DISH Network and the Chicago-Sun Times, but that will grow once people learn more about digital currencies.
"The biggest hurdle is education," Armstrong said. "But as more people learn about bitcoin and begin to see how it's a safer and faster way to transfer ownership online, we'll see adoption increase across the board."
FULL LIST: 2014 CNBC DISRUPTOR 50
CORRECTION: This version corrects that the Accenture report said banks could lose 15 percent of market share to technology companies by 2020.