One of the GRS (Gamma Ray Source) systems closest to Sag A* is a quadiary(?) Black Hole system, with nothing else there.For me it would be a binary Black Hole system.
Search for GRS in the Galmap, the one in question is roughly at 2000,22000,500 (going from memory). The system was quite valuable even though I'd left my DSS at home to make room for a present that I delivered to CMDR Metta. It's quite close to Great Annihilator as well, so it's worth visiting if you're in the area.
I'm planning to go back there if FD ever implement accretion disks, because all the GRS systems should have an accretion disk as the strong gamma ray emissions are thought to be produced by a Black Hole or Neutron Star feeding from it's accretion disk.