As a composer, Stockhausen was a huge influence on the music I am currently writing. I am writing a piece in memoriam of him now. My composition professor/advisor told me about this yesterday when we were discussing my new piece. I was doing it in a style similar to "Stimmung", and I am deciding to put even more Stockie elements into it now.

As for living composers, don't forget György Kurtág, the composer of the "Kafka Fragments".

He will be missed greatly.

Thanks for those links above!