I would never put something in my brain that doesn’t at least have a public API documentation. If the company discontinued the product I want to be able to keep using it. Open Source software would be best.

I speak Esperanto and I am quite active in the movement and write for the Esperanto Wikipedia. In 2011 I had quite a cool trip to an Esperanto Youth Congress in Kijiv. But it’s hard to talk about it because most people see it as a failed project from the early 1900s, not as a modern subculture.