Let's think for a moment of how a church is organized; not the theological justification for its being, but the social models for its running. Business models are common; so are models from civil government. So too hints from organized labor and mass social movements. Sometimes these borrowings are conscious and obvious and others are hidden. Take a former mode of church finance -- pew rents and the chapel proprietorship -- that was clearly and undeniably a part of congregational polity churches at one time, but now is extinct and generally regarded as repugnant.
But one mode of organization that I don't see as direct influence in congregational polity churches is that of the economic cooperative, which apart from the equity inherent in a co-op, is such a familiar model for so many Unitarian Universalists that I wonder why it doesn't come any closer than the Memorial Society. (Then again, we don't have a history of denominational mutual aid societies, either. Perhaps this was siphoned away by Freemasonry, the influence of which has never fully been accounted among Universalists or Unitarians.)
Co-op organization is more than a four-hour stint at the organic food place across town, and I'm discovering ways and places the cooperative movement has touched that I never knew existed, such as the "social cooperatives" in Italy which began as a way of providing employment for consumers of mental health services as a part of deinstitutionalization.
Right now, I'd like some comment on the mechanism of church goverance -- congregational polity or not -- or experience readers have had with cooperative governance. I'll get to the theology later.