We have a custom at Midnight Mass on Christmas which invariably sends the shivers up and down your spine. Following Communion and before the final prayer, the lights go out so the church is lit only by the 16+ candles in the sanctuary. All 3 verses of Silent Night are then sung by everyone, all kneeling (fortunately most people know it by heart, since it's too dark to read in the nave). The first verse has light organ accompaniment, the second a cappella, the choir leading, the third with a little more organ. Then the lights come back on, the final prayer is said and the bishop gives the Christmas blessing, and the final hymn blasts out (usually either Joy to the World or Hark the Herald Angels Sing). A real smasheroo ending.