If you’re like me, you’ve probably been ignoring the bitcoin phenomenon for years — because it seemed too complex, far-fetched, or maybe even too libertarian. But if you have any interest in a future where the world moves beyond fossil fuels, you and I should both start paying attention now.

Last week, the value of a single bitcoin broke the $10,000 barrier for the first time. Over the weekend, the price nearly hit $12,000. At the beginning of this year, it was less than $1,000.

If you had bought $100 in bitcoin back in 2011, your investment would be worth nearly $4 million today. All over the internet there are stories of people who treated their friends to lunch a few years ago and, as a novelty, paid with bitcoin. Those same people are now realizing that if they’d just paid in cash and held onto their digital currency, they’d now have enough money to buy a house.