Twig Christmas tree decoration (have to translate page into English)
Clothespin Advent Calendar from Sunday in Bed. This link contains several other DIY advent calendars instead.
I'm totally against set seating, but you could put programs/photos etc in pinecones like this on ceremony seating.pine cone place card holders DIY project for fall or winter weddings
Yogurt cup punch it advent calander (from Marie Claire Maison)
tuto calendrier de l'avent en forme de sapin en bois et scrapbooking
DIY: Inspiration: Christmas advent calendar numbered packages tied to a branch. From La Petite Cuisine.
baby sock "advent calendar," thanks martha!
DIY Advent Tree from a pallet
DIY advent calendar using old Christmas cards, by Zoé de Las Cases