It doesn’t have a beat, the kids can’t dance to it, and it’s sung in a dead language, but Gregorian chant seems to be the hottest thing in sacred music right now. The wildly popular videogame “Halo 3” uses plainsong as background music. Universal Music, a secular recording company best known for rowdy acts like Amy Winehouse and Eminem, has just signed Viennese monks to record an album of Gregorian chant. British doctors are even reporting that singing the ancient chants have a powerful effect on reducing stress. Drawing on Pope Benedict XVI’s vigorous endorsements of Gregorian chant, the sacred songs are also experiencing a renaissance of sorts in U.S. Catholic circles. Scholas, or Gregorian choirs, are on the rise, recordings are flying off the shelves, and experts are reporting a renewed interest in the ancient music.