Through our art project, Metaphone, we explored a particular form of aesthetics referred to in the arts tradition as machine aesthetics. The Metaphone machine collects the participant’s bio-data, Galvanic Skin Response (GSR) and Heart Rate (HR), creating a process of movement, painting and sound. The machine behaves in machine-like, aesthetically evocative ways: a shaft on two large wheels rotates on the floor, carrying paint that is dripped onto a large sheet of aquarelle paper on the floor according to bio-sensor data. A soundscape rhythmically follows the bio-sensor data, but also has its own machine-like sounds. Six commentators were invited to interact with the machine. They reported a strangely relaxing atmosphere induced by the machine. Based on these experiences we discuss how different art styles can help to describe aesthetics in interaction design generally, and how machine aesthetics in particular can be used to create interesting, sustained, stylistically coherent inter...