I've seen these before but I've always stayed away because the costs for commercial licensing aren't spelled out or even estimated at all. I just never liked to anticipate the friction involved if I were to incorporate these into a project that would become a commercial endeavor.
If a not-for-profit entity like a library used one of these to make a T-shirt that is sold at a profit (but the profit goes to the non-profit) is that commercial use?
What if the design is done by a for-profit design firm for the non-profit library?
What if the non-profit library installs it on it's computers, and they get used by someone on a for-profit project?
Anytime you put a "profit" based limit on a license, you're probably doing it wrong. I'd much rather have a GPL style copyleft than this - it's less invasive.
