Vistaprint has 50 percent off on rack cards (these are the long cards you may have received as Christmas cards--people load their picture or select a picture from Christmas themes and create cards).
http://www.vistaprint.com/rack-cards...53286092&GNF=1
STOCKUP
They sell actual Christmas cards too, but I think those cost more. Since I order rack cards as bookmarks to give away, I can tell you that you can create the same sort of thing as a postcard and the postcards usually run cheaper (you can do front and back--they are blank--they don't have the lines for text that some postcards do). You may have to buy special sized envelopes if you intend to mail the postcards. The rackcards fit in a regular business sized envelope.
They also have calendars that you can create using your own pictures. We've received these as gifts. I don't know if the coupon works with those or not, but 50 percent is pretty much the best coupon I ever get from them.