20 December (releases)


 * 1975 - Part three of the TV Comic story The Dalek Revenge was first published.
 * 2010 - The Korven was first broadcast on Disney XD.
 * 2010 - Part five of Snowfall was first published online.
 * 2011 - Part one of Attack of the Snowmen was first published online.
 * 2011 - The beta version of the video game Worlds in Time was released by BBC Worldwide.