Smart-Its, a tool kit developed to create a physical construction for distributed applications, makes it possible to sketch hardware effectively. Smart-it is a stick on computer that can be attached to any object. It features a number of sensors, a microprocessor, some memory and a radio. Each device can collect data from the environment, run its own code and communicate with other Smart-Its and external servers. Smart-Its determines the progress of the process and focuses on the next step or warns against the errors. The capability to build a physical mock-up and augment it with interactive behaviors will become essential for product designers. It is necessary for the design profession to come to terms with the fact that interactive behaviors, those made possible by Smart-Its may become an integral part of their work.