Incorporating a cluster of items create depth and value of texture to the eye. There is nothing better than volume and variance of colour to get someone's eyes to pay particular attention to a focal point. More often than not we cluster items into the corners of rooms and on book cases - but we don't have to limit ourselves like that. Using a bit of creativity and picking up some objects it is actually very simple to play around with height, texture, colour and volume to bring ambiance and character to a coffee table or surface of your choice.
-Manny