Obviously, you need contrast. Don't go for stark contrast; instead of bright white, go with a blonde or offwhite and use fabrics to blend the two together.
Keep the furniture color light, so that they don't disappear into the walls. Beige, pink, aqua, red--all would look great. Think of the brown as "chocolate".
You want to find furniture that is light in color. Some examples might include: white, beige, light blue, light yellow, or even a pale pink color. When you go furniture shopping try and take a sample of the brown that is on your walls. This way, you can see if the colors will clash or not.
Creme color furniture would compliment dark brown walls, and would give the illusion of making the room larger. Choose furniture that is very light in color and over-sized to lighten the rooms atmosphere and make the room comfortable. Wood or metal accents on the furniture should also be light in color.
The furniture which you can choose for matching with the color of the walls can be of a light shade. You can go in for ivory color or peach color. If you want you can select light biscuit color also.