Product design is most often about building order and predictable functions into objects. There exists however a fascinating array of products that possess some purposeful disorder and unpredictability. These products embrace the concept of randomness and interaction with such products brings an experience of being out of control. This paper discusses the concept and application of randomness in product design through a two-pronged methodology: partly a survey of prior academic art and partly an analysis of twenty products. The findings show randomness to be exhibited in products for a variety of reasons: entertainment, security, ambient effects, and gambling. From the findings, general suggestions for how to integrate constructive randomness into products are made. The primary purpose of the paper is to act as a stimulus for designers, researchers and educators, giving insights into a product attribute that has good potential for more widespread application in future products.