We have a church in our area that does a yearly Christmas program that has grown so big that they had to move to I-Wireless Center. They sell out the theatre 4 nights.
They do charge, many tickets are given away by their congregation to people they invite.
The "Littledrummer boy" in the video I am posting is different every year, but always a crowd favorite.
It starts with one drummer and builds and builds to a great crescendo.
http://www.youtube.com/watch?v=vdikl88ntBE