If Christmas and New Year's Eve parties unfortunately have to be cancelled this year, perhaps it's time to remember an old rule: It doesn't take a special occasion to drink first-class wine. The wine itself becomes the occasion. This is no less true for the sparkling versions than for still wine, at least when it's really good. And what better way to illuminate a temperate mood than with a decent champagne, the finest spumante, vintner's sparkling wine or cava? This also works in the smallest circle, in an emergency even alone.