In a recent session of our Visual Development class Kristen Robertson did a nice job on an assignment she was given to create a variety of different moods for a background composition she created through the use of planned color schemes. Her medium was color markers. Each study evokes a unique feeling. By applying basic color theory the single composition becomes differing versions that imply time of day and emotion as well as design abstractions. A very good exercise. See more of Kristen's work by following this link to her blog.