As you know, great paint colors don't just happen by accident or guesswork. There really is a science to selecting a hue that does wonders to a room. Here is another example of how chosing either one or two colors to use in a space can make a big difference in how you perceive its size.
In this example a foyer can either be visually included in the larger room or separated to give the impression that there are more functional areas to a home. This is especially useful, for example, in eat-in kitchens where there is one large room to serve two functions, cooking and dining. Painting a wall (or adjoining walls) near the table in one color and the opposite walls in the cooking area a complimentary color divides the space nicely.