The movements of the lanky man on the videotape mesh perfectly with the undulating rhythms and cascading tones that accompany his dance. As the music swells, his gestures grow pronounced and emphatic; as the sound dwindles to the pulse of a synthesized bass or the flutter of an electronic clarinet, his motions diminish to the twitch of a hand or the slow sweep of an arm. The choreographer, it seems, must have worked closely with the dancer and the composer to make such a seamless piece. The reality is more complex: This dancer is, in fact, also choreographer and composer, choosing his moves on the fly while simultaneously making the music to match in an intimate collaboration with a video camera and a homemade computer system.

Sprawled shoeless on the living room floor in his Toronto home, 38-year-old David Rokeby watches the 28-year-old version of himself on a small TV set. Though his worn jeans, wire-rimmed glasses and only slightly scruffy hair make him look like the math professor his parents wanted him to be, Rokeby has instead become an internationally known interactive artist-his multimedia installations invite gallery goers and exhibition attendees to become active participants in the artistic process.