When galaxies collide, they produce some impressive displays. They also can produce quite a few new black holes. A recent press release from the Chandra X-ray Observatory provides a beautiful example of this phenomenon.
NGC 922 is a nearby galaxy undergoing some extreme star formation due to a recent interaction. The above image is a composite from the Hubble Space Telescope and the Chandra X-ray Observatory. The bright red blobs are X-ray point sources, mostly black holes. The press release linked above contains more details, but for those really interested, you can find the paper at this link. (Caveat: Wesleyan professor Roy Kilgard is a co-author on the paper.)