pro bono: from Latin pro bono publico ‘for the public good.’
In the etymological sense, I consider all of my work pro bono. But I am also concerned to make available resources that can be shared (with proper credit, of course) for the public good. One of my great privileges in recent years was creating (with a lot of help from Notre Dame's Office for Digital Learning!) a free online course, The Meaning of Rome, now archived online on the edX platform.