Sviatoslav Richter, considered one of the greatest pianists of the 20th Century, would have celebrated his 90th birthday last month. In a field full of eccentrics, Richter was still regarded as particularly unpredictable and moody — and one of the most enthralling performers who has set foot on a stage. Sara Fishko looks at the fiery phenomenon of the Russian pianist and his effect on a generation of music-lovers.