That's a great question. I've always been partial to "FSF certified" and "OSI certified". Put it right on the organizations that promote the definitions. And it gets those groups extra exposure when people look the terms up. Bonus: we could then pretend FOSS stands for "FSF/OSI Sanctioned Software".
They could even get trademarks on those terms, unlike the failed attempt to trademark "open source".
> I think it deserves to be addressed.
We've gotta get people to budge on this, and see things from the other side. Find a way to do that and I think you could achieve world peace =)