Silver Devastation

The Silver Devastation was an area of space in the Isop Galaxy where two galaxies collided some hundred billion years ago. This vast sector of space contained nothing but dead stars and dark matter. From a great distance it looked like a huge silver sea hanging in space, the edge area being commonly referred to as its "coast". (PROSE: The Game of Death) Another source stated the region of space was all but obliterated in the 20th century by an entropy field event. (AUDIO: Cold Fusion)

The Face of Boe was said to be from the Silver Devastation. (TV: The End of the World)

Professor Yana was found as a baby on the coast of the Silver Devastation, a naked orphan in the storm with nothing except for a strange fob watch. (TV: Utopia, AUDIO: The Heavenly Paradigm)

Serenity was a planet in the Silver Devastation. (AUDIO: Cold Fusion)

The Tenth Doctor encountered an asteroid that shouldn't have been in the middle of the Silver Devastation. It contained blood-sucking monsters from another universe. (PROSE: The Game of Death)

Behind the scenes

 * Russell T Davies stated on the Utopia DVD box set commentary that Yana's memories were true. Davies said of this backstory: "He was a baby. A human baby. Because that's what the Master did — he was so frightened and terrified that he wiped himself as a baby and found on the Silver Devastation." Years later, Scott Handcock convinced Davies to reconsider this statement, as detailed in DWM 519.
 * The audio story The Heavenly Paradigm later depicted the Master using the Chameleon Arch and becoming a baby, definitively.