Before 21 Inc. had even put out a product, it had raised $121 million in venture funding—the most of any bitcoin company. It was unclear, for months, what 21 would actually do or make. But some of the biggest names in fintech funding, including Andreessen Horowitz, Khosla Ventures, and the Winklevoss brothers, were interested enough to invest.

Then things started to move very quickly. In February, 21 released its first product—and it was hardware, a rarity among bitcoin companies. It was the 21 bitcoin computer, which allows for mining the cryptocurrency as well as building applications on top of the bitcoin blockchain, the open-source, decentralized ledger that underlies bitcoin.

The computer, which runs on Raspberry Pi (a small, single-board programming computer launched in 2012), sells for $400 and is about the length of an iPhone. It attracted a lot of buzz and attention in the bitcoin world.

The 21.co bitcoin computer More

Last week, at the bitcoin conference Consensus, 21 CEO Balaji Srinivasan, a partner at Andreessen Horowitz, moved the company’s purview forward again. He announced that the 21 software can now be installed on any Mac or Linux-compatible system (Windows is coming soon), and eventually will come to mobile phones. “Every computer is now a bitcoin computer,” he said.

And this is why 21 is arguably the single most exciting bitcoin company right now.

Most people on Wall Street, as well as regular, everyday investors (and Yahoo Finance readers like you) still don’t quite understand what bitcoin is, or why it matters. Many think it’s a scam or some kind of illegal tool for hackers. (The negative publicity around stories like the Silk Road trial didn’t help.) Srinivasan’s argument is: You don’t need to know what it is or how it works for it to be important to your digital life. He explains it this way to a layperson: “I ask people, ‘Do you use Linux?’ They’ll probably say no. But if you’re using Google.com, or Facebook.com, or Yahoo.com, you actually are using Linux, even if you don’t know it. So Linux is there, everywhere, it’s just behind the scenes, and it just sounds very technical because it solves problems for developers. And I think it’s going to be the same thing with bitcoin.”

Srinivasan frames bitcoin as the next major “system resource” in computing, something that will be a key component in every computer, just like a hard drive, RAM, and bandwidth. Bitcoin, he says, can be the resource that computers trade with other computers (without you having to worry about it), creating a “machine economy.” Once a computer can send a small amount of money as part of its operating system, “it can effectively rent or sell resources to other computers,” Srinivasan says. That was the idea behind the bitcoin computer: “If you had 500 of these things, what could they do together?”

So, what can they do together?

For starters, you could earn a small amount of money (yes, in bitcoin, but a wide range of platforms now exist for quickly converting bitcoin to U.S. dollars, if that’s what you’d prefer) every time you visit a certain URL. On stage at Consensus, Srinivasan described it thusly: "Every time you load a webpage is a HTTP request. That’s a lot of HTTP requests. If you are earning bitcoin on every HTTP request, that could be a lot of earned bitcoins."



Story continues