Tell ya something that I've been using lately. You guys probably already do this and don't need to be told, but I've bought several tablerunners at the Goodwill lately and they are wonderful for covering my "mantle" shelf. Got a pretty neutral colored one today with a lot of texture in it. Probably gonna do a white, cream and wood/nature type display on it tomorrow.
Bought a white lace valance that I used for awhile with all white things on it. Then changed all the items to all black.
Also have a red/white/yellow floral summery looking one. Hanve't used it yet.
I don't have them for sale - just stick them back and interchange some of them to go with what I want to display.