The intracluster medium in cool core clusters of galaxies must be energized by feedback from the central AGN but the physical mechanism is unknown. The central AGN is usually surrounded by a system of filaments which appear similar to those in the Crab Nebula. The filaments have a very unusual low ionization / molecular spectrum and are not powered by starlight. I will describe our investigations into the origins of the filaments and their power source, and what role they may play in the feedback process.