More ideas,

My second idea is to create a set of possibly 4 or more separate interactive pieces. These pieces will have a different type of interaction IE sound responsive, galvanic skin response, touch response or visual response. and each one in turn will have a different type of reaction to these input which would be either visual lights, patterns or shapes or audio music or noises.

so the skin response would maybe out put a sound to make the skin response vary depending on the type of sound played back for example.

or another example would be tracking the eye movement of a user and using the pattern to create an image on a screen.