A recent summit meeting of Minnesota nonprofit companies was a fairly dismal affair, with executives from the state’s biggest arts groups bemoaning the downturn in public and private financing. But at least one corner of the nonprofit sector is raking in the dough – in Minnesota, HMOs and other health care companies are non-profits, too. It makes for an interesting contrast, since the skyrocketing cost of health care is one of the factors causing so much suffering at the state’s larger arts groups.