In 2016 I created a video course to help people learn D3.js. On top of the course material, I designed and built a platform to sell the course. Building this really pushed me outside my comfort zone, but what I gained was well worth it. I learned valuable marketing, video, writing, product development, and back end skills.
It's an empowering experiance to build a concept from the initial idea and then execute at every level. You can learn more about the course on the landing page.