My business is finally taking off after about 5 of working "FREE" whats the best way to call this PRO BONO?

I have friends that are attorneys. When they take a case without expectation of being paid, they call it "pro bono" - so that is what I think of when I hear the term. It is certainly not something they make a habit out of doing. It is working for someone else for free, not working for yourself.