One of my very best girlfriends let me take these pictures of her fabulous artwork in her home. It's just long strips of wallpaper adhered to the wall then she painted some small wood trim to go around it. It covers a large area (floor to ceiling) and is as wide as a roll of wallpaper, you could even do a couple right next to each other if you had a larger space to fill.
This is a closeup of the wood trim around the edges.
I love this idea it's so inexpensive and if you wanted to change your decor just take it down and put up another design.