I just watched a show on the science channel. The Nukers (a group of scientists) have discovered that all galaxies have black holes at their center. Even OURS!
Supermassive black holes, they call them they also said it is possible ours is starting to feed again. Utilizing the Hubble they have been able to determine it's precise location and some characteristics.
http://science.discovery.com/tv-schedules/...13781.23567.0.0
http://www.noao.edu/noao/staff/lauer/nuker.html