While critics are still dubious of the future viability of the digital currency bitcoin, at least one group isn’t: venture capitalists. VCs pumped more investment into bitcoin and blockchain-related startups last year than in any previous year—nearly $1 billion.

The investors are keeping this industry hot, even if we haven’t yet seen any so-called “killer app," a mainstream use case for bitcoin that would compel the average person to care. And it isn’t just investors leading the charge—it’s a handful of key executives, thinkers and even policy people.

Of course, investors are just as keen on companies exploring the blockchain, which is the decentralized ledger technology on which bitcoin runs. (For a full explainer on blockchain, watch this video.) The hype around the idea of banks using a form of blockchain (without bitcoin) is high, even though a PwC survey this month found that 57% of financial executives say they're “unsure” about implementing blockchain tech in banking.

So, who are the big believers? They are some of the biggest names in bitcoin and blockchain right now. Some are executives at the most well-funded companies, some are investors in those companies. All of them bring clout and connections to bitcoin and the blockchain. Here are 11 of them, curated by Yahoo Finance with input from a number of industry insiders. This is not a list of the hottest bitcoin companies, nor is it a ranking. It’s an unofficial look at the individuals bringing mainstream attention to this still-nascent, still-controversial corner of tech. Call them the "bitcoin celebrities" if you like.

This list is unranked (alphabetical order). Feel free to debate, dispute and make your own suggestions in the comment section.

1. Marc Andreessen, Andreessen Horowitz

Everyone in tech knows Andreessen. He is the co-founder of Netscape, a board member at Facebook, eBay and others, and co-founder of the Silicon Valley powerhouse venture capital firm Andreessen Horowitz. The firm’s portfolio includes investments in bitcoin wallet company Coinbase (see No. 6), 21 Inc (see No. 9), and TradeBlock. In 2014, he wrote an op-ed in the New York Times boldly titled, “Why bitcoin matters.” He liberally shares bitcoin and blockchain-related news to his 500,000 Twitter followers—a considerable benefit to bitcoiners.

2. Brian Armstrong, Coinbase

When Coinbase, one of the earliest bitcoin startups, raised $75 million in funding in January of last year, it was at the time the biggest fundraising round ever for a bitcoin company. (The figure has since been shattered by 21 Inc.) And Coinbase, which has raised $107 million total, remains arguably the best-known name among all bitcoin startups—it is often where people go to get a bitcoin wallet and to buy their first bitcoins. It was first to market with a bitcoin exchange platform in the U.S. (others waited longer in order to get certain licensing) and Armstrong, its leader, is one of the most sensible thinkers in the industry. (His post explaining the debate over block size distills the issue clearly.)

3. Adam Back, Blockstream

Bitcoin is partially based on a previous system called hashcash, an algorithm that cut down on email spam by requiring proof of work, an early form of what is now bitcoin “mining.” Back created hashcash. Now the cryptographer, as president of blockchain startup Blockstream, has become one of the loudest voices in the debate over whether, and how, to increase the size limit of transaction bundles (or “blocks”) on the bitcoin blockchain. His experience in business (he's worked as a consultant to Nokia) and in academia (he has a PhD in distributed systems) have made him a unique authority in the space. Reid Hoffman, the influential co-founder of LinkedIn (LNKD), made a personal investment of $21 million in Blockstream, and the company has raised $76 million overall.

4. Vitalik Buterin, Ethereum

Ethereum is a bitcoin alternative that some believe has more potential than bitcoin. The platform runs on a decentralized blockchain, like bitcoin’s, that allows for any peer-to-peer exchange of value, and it uses its own currency, Ether. And the company is a non-profit. Buterin developed the concept in 2013, and in 2014 sold about 60 million ether in a pre-sale, which worked out to $18.4 million at the time. The Ethereum chain went live last summer. Buterin, who is only 22, is seen as a wunderkind; he also helped launch Bitcoin Magazine.