I've been building Historai for a while and finally shipped it. You type any moment, person, or object from history and it researches and narrates a real episode about it, two hosts, visual slides, the works. The part I'm proudest of: you can interrupt the episode at any point, ask the hosts a question, they answer, then pick the story back up. The thing podcasts have never been able to do. It started because I kept wanting to learn about specific things and couldn't find a podcast for them ...