We're saying it now -- Saturday afternoon at Caffe Trieste should also be known as the People's Opera. As basketed Chianti passes from glass to glass in the back row, the singer puts the microphone to non-operatic use. "Hey, is the hot chocolate ready for this young man?" she asks, harassing the baristas. The kid in question squirms, embarrassed but pleased, as everyone laughs. Of the two accordion players, only one is a Caffe owner -- the trumpet, piano, flute, bass, and banjo players are all just friends. At least three generations are in evidence in the audience, from perfectly coiffed grandmas to baby boomer dads to tiny, sleepy babies, all enjoying an afternoon of live opera. The singers aren't strict about their genres, though, and offer up some country and western ("Crazy," of course) and show tunes in addition to the aria from Carmen and "Italia Mia." There's one catch: All drinks cost $5.75, minimum, from 2 to 6 p.m. Might as well get the Chianti.