I learned from the Nester that practically anything can go on your walls. An old door. Plates. Shutters. Whatever. While I haven't been brave enough to ask James if we can tack a door onto the wall, I have added many plates to our bare and undecorated walls. I found a few at thrift shops and some in the clearance racks of my favorite stores. Putting plates on the wall is cheap, pretty, and unique--perfect for a Spartan like me.
This grouping is in my dining room, as are these: