Whenever I hear about some open source volunteers who "did the hard part" and then someone else came along, "slapped a GUI on it" and made big bucks, I wonder why the original developers didn't bother to do that part. Maybe the real value isn't where a lot of people think it is.

After reading all these stories, I conclude that if you build only infrastructure you are going to get nothing back. Maybe the DHH approach is better: Build an app and then factor some infrastructure out of it later.