The first one that comes to mind is Qt (the widget toolkit). While I’m not sure the current owners still do this, Trolltech offered the earlier versions under both the GPL and a commercial license that I think included paid support. I assume any sales under the commercial license were to companies who wanted to include it in their closed-source software.
Do you have an example of a project that has both free and commercial licenses? How does that work in practice?
I don’t know of examples of dual licensing (maybe redhat?) But Wordpress is a GPL project that still has an industry around it
The first one that comes to mind is Qt (the widget toolkit). While I’m not sure the current owners still do this, Trolltech offered the earlier versions under both the GPL and a commercial license that I think included paid support. I assume any sales under the commercial license were to companies who wanted to include it in their closed-source software.