A human black hole, in the DC Universe. First appeard in Flash (second series) #9.
Chester P Runk was a highly intelligent, but overweight, young african-american man. At school, the other kids called him "the Chunk" and shunned him. He had difficulties dealing with the taunts, and received therapy to try and deal with his insecurities, all the while studying the physics of singularities at an incredibly high level.
In pursuit of a scholarship to study at MIT he built a matter transmitter, using the properties of singularities. Unfortunately, on his first attempt to use it it blew up and imploded, and Chunk mistakenly swallowed it. That's right - he swallowed it. Accidently.
Following this unlikely accident, Chester took on some of the properties of a black hole himself. He was already black and round, but now he could control his own personal gravity, and suck things towards him. He could also absorb things and people, sending them to another dimension, a barren wasteland inhabited at first only by strange flying lizard creatures.
Chester sent many people to this strange wasteland. Some were people that had made fun of his weight, or otherwise slighted him in some way, and some were violent thugs that Chester had deliberately provoked. He soon found out that he actually needed to consume a certain amount of matter every day to avoid imploding, and being sent to the dimension himself, and from there to successively worse dimensions. He became unbalanced, and began to use his powers to steal and absorb dense, precious materials such as gold, platinum and diamonds, calling himself the name that had been used to taunt him at school - Chunk.
Chunk encountered the Flash during one of his robberies, and sent Flash to the wasteland dimension. There, Flash met the other people Chunk had sent there, who had adapted to the harsh conditions as best they could, one group making a camp, hunting the flying creatures and growing plants from seeds found in car boots, the other group eating whoever they could catch in the first group. Flash eventually convinced Chunk that the world would forgive him for sending people to a bizarre other world once he showed them his work on the matter transmitter, as long as he sent everyone back home.
Chunk did manage to get everyone out of the wasteland, and Flash managed to keep him from being arrested. Chunk eventually started up a waste disposal business (yeah, that's right, a highly intelligent black man and the best job he can get is a garbage collector; how's that for biting social commentary?), and he and Flash became good friends.
As an interesting side note, at one stage Chunk sends two scientists on a little tour of some of the dimensions he can access through his powers. After returning from their tour of a number of barren, inhospitable wastelands, the scientists speculate: "It's as if an infinite series of worlds, just like Earth... all inhabiting the same space-time continuum, had been crushed together and destroyed in some unimaginable cataclysm!" Sound familiar?