I will present recent observational results on the nature and origin of the multi-phase interstellar medium
(ISM) in giant elliptical galaxies, and its role in galaxy evolution and in fueling the central
supermassive black holes. Our results show that the cold gas in these systems is produced chiefly by
thermally unstable cooling from the hot phase, and that active galactic nuclei are likely to play a crucial
role in clearing giant elliptical galaxies of their cold gas, keeping them 'red and dead'. Then I will
'zoom out' to the outskirts of galaxy clusters where we also find hints that supermassive black holes
played an important role in the distant past. X-ray observations with the Suzaku satellite reveal a
remarkably homogeneous distribution of iron out to the virial radius of the nearby Perseus Cluster,
requiring that most of the metal enrichment of the intergalactic medium occurred before the cluster formed,
probably more than ten billion years ago, during the period of maximal star formation and black hole
activity. Finally, I will talk about the upcoming Astro-H mission which will revolutionize X-ray
spectroscopy and our understanding of the dynamics of the intra-cluster medium.
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