You may be saying "WHO?!" but Ligeti was one of the most avante garde, intelligent composers of all time. I knew him for his work with Stanely Kubrick, especially that CREEPY music that came from the monolith in 2001: A Space Odyssey.
(edited by Parts Unknown on 13.6.06 1258)
"How could we possibly appreciate the Mona Lisa if Leonardo had written at the bottom of the canvas: 'The lady is smiling because she is hiding a secret from her lover.' This would shackle the viewer to reality, and I don't want this to happen to 2001." - Stanley Kubrick