[Quot]

Just off the top of my head,

Aseprite: https://github.com/aseprite/aseprite Onivim: https://v2.onivim.io/ Ardour: https://ardour.org/

Of course, I don't know how successful each of those projects are, but they seem to be successful enough to continue development.

[EduardoBautista]

First one is not an open source and the other two don't appear to be businesses.