On today's episode, we ride through the streets of San Francisco with a long-time junkman, Jon Rolston. Jon has spent the last two decades clearing out houses and offices of their junk. He's found all sorts of items: a life-time supply of toilet paper, gold rings, $20,000 in cash. Over the years, he's developed a keen eye for what has value and what might sell. He's become a kind of trash savant. As we ride with Jon, he shows us the whole ecosystem of how our reusable trash gets dealt with — from metals (ferrous and non-ferrous) to tires to cardboard. And we see how our junk can sometimes get a second chance at life. If you can understand the junk market like Jon, you can understand dozens of trends in our economy. This episode was hosted by Erika Beras and James Sneed, and produced by James Sneed with help from Emma Peaslee. It was edited by Jess Jiang. Engineering by Josh Newell. It was fact-checked by Sierra Juarez. Alex Goldmark is Planet Money's executive producer. Help support Planet Money and hear our bonus episodes by subscribing to Planet Money+ in Apple Podcasts or at plus.npr.org/planetmoney. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Last month, the world narrowly avoided a cyberattack of stunning ambition. The targets were some of the most important computers on the planet. Computers that power the internet. Computers used by banks and airlines and even the military. What these computers had in common was that they all relied on open source software. A strange fact about modern life is that most of the computers responsible for it are running open source software. That is, software mostly written by unpaid, sometimes even anonymous volunteers. Some crucial open source programs are managed by just a single overworked programmer. And as the world learned last month, these programs can become attractive targets for hackers. In this case, the hackers had infiltrated a popular open source program called XZ. Slowly, over the course of two years, they transformed XZ into a secret backdoor. And if they hadn't been caught, they could have taken control of large swaths of the internet. On today's show, we get the story behind the XZ hack and what made it possible. How the hackers took advantage of the strange way we make modern software. And what that tells us about the economics of one of the most important industries in the world. Help support Planet Money and hear our bonus episodes by subscribing to Planet Money+ in Apple Podcasts or at plus.npr.org/planetmoney. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy