Purple is THE hot color right now! But first things first, what is the function of the room? You'll want different accessories for a bedroom vs. a home office, etc. In general, hanging art is always a great way to break up a dark wall. As for dark purple—bright yellows, reds and oranges really pop against a dark purple background. Choose a color pallet that appeals to you and buy accessories that match those colors. For ideas, check out these slideshows on decorating with color: http://www.bhg.com/decorating/color/. Happy Decorating!