If you have a large blank wall that you don't know what to do with, consider framing wallpaper! Get some trim molding cut to the proper size at Home Depot and paint it white. This makes for a dramatic (but inexpensive) piece of wall art.
There are more pics of grey and yellow spaces where this one came from. I really like the idea of using grey and yellow for a bathroom or a bedroom. The grey makes the space look larger while the yellow warms it up and gives it a happy, cozy feel.