No one knows for sure whether Bitcoin is a currency or a means of transferring funds.

In his new note on Bitcoin, Bank of America Merrill Lynch currency analyst David Woo buys into the argument from Bitcoin evangelists that the digital currency can be both.

And in discussing its value as a means for wiring money, Woo goes big.

Some background: When discussing Bitcoin's potential value, people often use the example of a migrant worker in the U.S. using Bitcoin as an alternative means to send remittances home. There are no known examples of this happening yet — as with many things bitcoin, this is pure speculation — but it's technically possible.

There is also speculation that this use is one of the reasons for bitcoin's extreme growth in China, since the country's capital controls make it difficult to perform transactions overseas using yuan.

So Woo draws up a very bullish comparison between bitcoin and Western Union, MoneyGram, and Euronet, the world's largest wire transfer companies. He frames it in the context of those companies' market cap (or enterprise value, which includes debt), and compares it to Bitcoin's market cap, which is now $13 billion.

"Let’s assume that Bitcoin becomes one of the top three players in this industry. What does that mean for Bitcoin valuation? Given Bitcoin’s supply is fixed, when one buys a Bitcoin, one is acquiring not only a medium of exchange but also an investment in the enterprise value of Bitcoin. From this point of view, Bitcoin's market capitalization could be viewed, with a little leap of faith, as its enterprise value. With the average market capitalization of Western Union, MoneyGram and Euronet at about $4.5bn, we will add this number to the maximum market capitalization of Bitcoin’s role as a medium of exchange."

So bitcoin is technically already worth nearly three-times as much as the average market cap of the big three wire companies. Woo includes a chart comparing bitcoin specifically to Western Union.

"Assuming Bitcoin becomes (1) a major player in both e- commerce and money transfer and (2) a significant store of value with a reputation close to silver, our fair value analysis implies a maximum market capitalization of Bitcoin of $15bn (1BTC = 1300 USD)," said Woo.

More fuel for the frenzy.