(Photograph) - To accompany an exhibition of 72 of his drawings last month Michael Heindorff (above), senior tutor in painting at the Royal College of Art, produced an interactive catalogue on CD-Rom. Manfred Pfeiffer, whose German company sells software for processing dental X-rays, helped on the technical side. The minimalist CD uses no sound, animation, computer typography or colour. "We worked for three weeks just to get the greys right," the artist said.