Lots of developers spend hours coding free and open Libraries. Avoiding entering the fairness or motivational issue for the sake of objectivity, what I would like to do is charge 1% of the profit of whoever use my Lib.
I want people to be able to publish their app using my Lib, without asking me for permission or having to close a deal or pay beforehand.
Still, I want to let my code open on Github so if someone wants to clone or improve they would be able too. So my code would still be open source but not free under commercial situations. ( I cant figure out how to deal with forking issue, but lets save this case for later)
I have no intention whatsoever of sue the developer/company if they don't pay. But I believe it is only fair I ask for the pay of those who profit with the lib. This is the framework i adopt when profiting, giveback to the community.
Finally, the question is: Is there currently a model like this? Case not, What would be the way to do it, should I mod an existing license?
EDIT
I don't see how my question is not related to Software development, while this one fits: http://stackoverflow.com/questions/3828477
EDIT2
Thanks @David Thornley +1