Today I decided to listen to some pieces I hadn't listened to in a long time, and there he was, in the bottom of huge pile of CDs and scores, Ligeti. Right now I'm listening to his Chamber concerto for 13 instrumentalists and I realize: I like him even more than before.
Other important Ligeti suggestions:
-San Francisco Polyphony
-Etudes pour piano (3 volumes)
-both his String Quartets