Johannes Kreidler is documenting a vast assortment of graphic music scores on his http://www.kulturtechno.de/ This is an important catalog for all interested in finding a different voice in compositional construction.
Many of these scores, I have not been exposed to and I have been sharing them with others from his postings. This is great work and a unique service and gesture to all of us interested in our unique path of musical endeavors.
Don't miss his music either. He is a disruptively, radical thinker. He has a game changing mind set which is evocative and essential.