Our tradition the last few years, is to add a white candle in the center of the Advent Wreath. It sits unlit through the four weeks of Advent and is lit on Christmas Day. The other candles stay unlit after the "waiting" is over, and there wasn't much left of them anyway. I really enjoyed this white candle for a few weeks after Christmas. It added beauty to our table and was so pretty burning in the evenings.
Christ is the Light of the World! He overcomes the darkness.