John Cale & Terry Riley - "Church of Anthrax"
Terry Riley was among the pioneers of minimalism (along with Steve Reich and La Monte Young). He published and performed "In C" in 1964. Many other versions would follow, and In C's mathematical approach to improvisation not only set the groundwork for minimalism, but influenced many other genres as well.
In 1971, Cale and Riley released this collaboration which somehow sounds like both musicians while being very different from what either had done before. At times, the music recalls later Soft Machine. "Church of Anthrax" is a unique, hard to find record.