Maybe match christmas countdown sign? These are some of the most gorgeous free Christmas printables I have seen! I love, love, love chalkboard printables and the watercolor Christmas printables are gorgeous too!
DIY Gift for the Office - Sharpie Paint Pens Glasses - DIY Gift Ideas for Your Boss and Coworkers - Cheap and Quick Presents to Make for Office Parties, Secret Santa Gifts - Cool Mason Jar Ideas, Creative Gift Baskets and Easy Office Christmas Presents ht
If you don't have a fireplace, but still want to hang stockings and decorate a mantel, you can craft one out of cardboard! Using cardboard display boards (ones students use for science projects), you can build a realistic (and lightweight) fireplace.