As John Gomez, MD, owner and medical director of RapidMed Urgent Care Center in Lewisville, Texas, points out, to transfer bitcoins from one person to another, there are "zero transaction fees. Zero. It's beautiful."

And there were no startup costs, because his office already had an iPad for other purposes. (One possible problem may arise there, as Apple has recently been removing bitcoin-related programs from its app store.)

Gomez's office manager, Barbie Fiorendino, says no patients have yet used bitcoins to pay for service, but customers are expressing curiosity and interest in the prospect – especially since a local television station did a story about the clinic and bitcoins in January. The clinic distributes printed literature with explanations, and also has a bitcoin section on its website.

Unlike Abramson, Gomez is not planning to convert his payments out of bitcoins. His accountant, who was "very open-minded" about him accepting bitcoins, said he should book his revenue as dollars according to the bitcoin exchange rate at the time of the transaction – and keep records for future years, when he might convert the bitcoins he received back into dollars.

At that time, he would have to calculate capital gains or losses for tax purposes.

His decision to keep his holdings in bitcoins is "a personal belief," he added. "I consider myself a future rich man" because of bitcoins' value prospects, he said.

"There will be ups and downs and there will be potential manipulations," said Gomez, but "in the long run, I think that it's a smart play."

Gomez is more enthusiastic about bitcoins than Abramson – perhaps even qualifying as somewhat of an evangelist.

"I am, generally speaking, an early adopter of technology," Gomez said. Beyond that, "I have certain, I guess you would say politically libertarian leanings," he said.

He is among the many bitcoin enthusiasts who are particularly excited about the existence of a relatively secure currency that is not controlled by a government or other central authority.

Rather, the Bitcoin system is managed by software and mathematical principles, and is made possible by a peer-to-peer network that shares the burden of tracking bitcoins to ensure nobody counterfeits any, or spends the same bitcoin twice.

"It is an abstract concept at first," Gomez admitted – but said that's really no less foreign than the idea that swiping a credit card is a functional stand-in for exchanging dollar bills.

Meanwhile, government regulators are paying close attention, with several countries, the U.S. included, studying how to track – and tax – bitcoin transactions. How those regulations shape up will likely determine the degree to which bitcoins become more widespread, Abramson said.

It's not always easy to use bitcoins, as Wall Street Journal writer Anne Kadet found when visiting various New York City businesses that take them.

"This took some doing," she wrote in January. At one point, using bitcoins was so technologically "cumbersome" that it was "looking like the worst currency ever."

But Gregory Levitin, MD, a Manhattan physician and assistant clinical professor of otolaryngology at the New York Eye and Ear Infirmary, believes bitcoins can help people improve access to medical care.

Levitin, who has patients around the world, was in India and not available for an interview. But in a December press release announcing his acceptance of bitcoins, he said he hoped the move "will open doors to treatment options and follow up care for patients the world over," by allowing them to use "a universal or virtual currency."

One area where Gomez and Abramson agree is the fact that bitcoins are not particularly useful when it comes to their business operations.

Gomez said he wishes more vendors and suppliers took bitcoins. (He has convinced the person who cuts his hair to accept them in payment, however, and he's also ordered items from Tiger Direct, an online retailer that accepts bitcoins.)

Likewise, Abramson says he has nobody with whom he can really do business in bitcoins. His landlord won't take them, and he has asked his employees if they want to be paid in bitcoins, but they have all declined.

There is, however, a cupcake store near his office that accepts them.