Regarding singing:
Years ago, when I was nine, someone in our class had a Christmas party. Maybe someone spiked the punch or maybe we were just sugar giddy from all the cupcakes, but we went around the neighborhood caroling at close to 11pm.
The people we startled or woke up were surprisingly okay with it.
So...maybe people in CA should go door to door caroling general religious songs and see if they can pick up people to join their troupe as they go along.
Or what about flash mobs? Just have people text people they know to meet at the pier or the parking lot of the galleria or whatever cool places there might be in California for such things and sing Handel’s Messiah.
Sounds like good ideas—maybe something a little easier to sing than Handel’s Messiah though. Amazing Grace, When the roll is called up yonder I’ll be there, Jesus loves Me, Ha Ha anything that most people know all the words will do.