Here are a few easy ideas for displaying your ever growing pile of Christmas cards. First one is the simplest - place them in a decorative basket in the living room or dining room for quests and family to look through.
Another idea is to make a hanging ribbon to attach them to. I took a thick piece of Christmas ribbon - and you can make it as long as you want - might need a few of them to hold all the cards. Use a suction cup with a hook to hang it up - I suctioned it to my ledges - and then using wooden clothing pins attach all the cards to it alternating sides for a more interesting look. You could also hang a few ribbons on a window or door side by side.
Another idea is to take off pictures or art work that you have on ledges in the house and display cards there - changing things up for the holiday season. That way they have a proper place in the house and its easy to see them!