With ''McMansions'' increasingly giving way to ''tiny'' houses, the desire to downsize and be more ecologically and economically prudent is a concept many are beginning to embrace. Focusing on dwelling spaces all under 1,000 square feet, TINY HOUSES (Rizzoli, April 2009) by Mimi Zeiger aims to challenge readers to take a look at their own homes and consider how much space they actively use. Ranging from tree houses to floating houses, TINY HOUSES features an international collection of over thirty modular and prefab homes, each one embodying ''microgreen living,'' defined as the creation of tiny homes where people challenge themselves to live ''greener'' lives. By using a thoughtful application of green living principles, renewable resources for construction, and clever ingenuity, these homes exemplify sustainable living at its best.