We developed Smart Furniture, which extemporaneously converts the legacy non-smart space into a Smart Hot-spot which consists of computational services. Since the Smart Furniture is equipped with networked computers, sensors and various I/O devices, it can provide various services by alone or by coordinating with other devices. In this paper, the physical structure and middlewares for the Smart Furniture are described. The prototype systems to realize Smart Hot-spot such as a Crossing Window System, an Active Authentication System for Library, a Mobile TV-phone System, and an Environmental Information Monitor System are also introduced.