Attending church services during the Advent season is a special time. Having been a part of different Protestant traditions, I must say that the ones that stick out in my mind are those involving the "Hanging of the Greens" and the lighting of the Advent candles each Sunday in Advent. This was a tradition in both the Disciples of Christ church I grew up in and the United Methodist church of my early adult years.
I've been to Christmas Eve candlelight services as well, and there is something beautiful about a simple worship service at this time of year.