Abstract: Super-massive black holes that grow at the center of dark matter halos distort the dark matter within their zone of influence into a steep density spike. Besides giving rise to strong enhancements of standard indirect detection signals, this spike can lead to qualitatively new windows into the physics of the early universe. I will talk about potential dark matter signals from the Milky Way's central black hole, some astrophysical caveats, and the possible use of black holes as dark matter accelerators.