It would be fascinating to see a complement to this thread, "Side projects that never got any traction". The tech press has a huge bias toward reporting on "what works" based on projects or companies that succeeded, without ever looking at the many projects and companies that do exactly the same things as the successful ones without ever getting anywhere.

I've been very successful in the technology world, including running my own scientific and software consulting company for many years, but as a novelist and poet I've been a complete failure, despite approaching the two in very similar ways. Maybe the markets are simply very different, or maybe it's just luck, or something else. So I think it would be interesting to see some side-by-side of projects that took off and projects that didn't.

There are lots of really interesting things people are posting here, but I bet for every success story there is a story of failure that involves a great many of the same elements, yet somehow never grew beyond the "that was an interesting way to spend my spare time for a while" stage.