Wainscot. While the space between the chair rail and baseboard can be finished as the rest of the wall (painted or wallpapered), many times the area is paneled. The options for the wainscot are many, including simple wood panels, beadboard, raised panels and horizontal wood paneling. And while the finish of the wainscoting can match the wood trim, it doesn't have to. For example, a painted wood baseboard and wainscot of simple, recessed panels works well with the stained wood window and door trim.
Though plate rails and picture rails have lost their utilitarian function, a trim line at the top of the window and below the ceiling is a powerful design tool. In addition to making a space more interesting and rich, this trim line can be used to establish a "datum" from which other elements such as soffits can be organized from, an approach used by architect Sarah Susanka and many other architects quite effectively.
Stow extra seating under a console. An easy way to squeeze in a few extra seats in the living room is by tucking a pair of poufs or stools beneath a console table — close at hand when you need them but easily tucked away.