A computerized interactor system uses physical, three-dimensional objects as metaphors for input of user intent to a computer system. When one or more interactors are engaged with a detection field, the detection field reads an identifier associated with the object and communicates the identifier to a computer system. The computer system determines the meaning of the interactor based upon its identifier and upon a semantic context in which the computer system is operating. One specific embodiment of the present invention is a bead interactor system that is a user playable sound and light show system. When an interactor bead is positioned within the detection space of the bead interactor system, a sound sequence begins and continues to play unaltered until the bead interactor is removed or other bead interactors are positioned within or removed from the detection space. Each bead represents a different sound and the row and column location of the bead within the detection space controls how the sound is modified, e.g., louder or softer, higher pitched or lower pitched, the period of play, etc. In some embodiments, the beads are translucent in order to conduct light from light sources located under each bead receptacle. The available sounds are determined not only by the identity of the beads and their positioning within the detection space and their associated states or orientations, but also by sound data stored in an accompanying computer readable medium. Hence a user can access a variety of sound collections by simply installing a different computer readable medium.