Eyes were popping at 7th and Montana yesterday as Rigolatte -- the man known for spontaneously breaking out into song when he's not busy laughing like a hyena or passing out biblical literature -- performed an impromptu version of The Marriage of Figaro in front of Our Favorite Starbucks. "There he goes, again," said one witness, "Singing opera." As if on cue, Rigolatte started waving his arms wildly from side-to-side. It looked like he was conducting an invisible orchestra, accompanied by strains of "Figaro ... Figaro ... Figaro" as he wandered down 7th Street. The whole thing left me scratching my head. Should I call the Met, or get the net ...?