We present ComposIt, a creativity support tool that assists designers in finding inspiration by providing many computer-generated examples. These examples may be beyond humans' imagination and thus are helpful to inspire users to create new ideas. To automatically produce examples, our system adopts the deconstruction and construction strategies that are commonly used in the creative industries. Given a 3D model, the model deconstruction module analyzes the model and divides it into several elements. Then the model construction module synthesizes examples by composing the elements from different models. To evaluate the effectiveness of our system, we conducted a user study, in which artists were invited to design using our system. The results conclude that our system is able to inspire artists in their design process. The artists also shared their usage experience of our system in various aspects.