A new term describing a FanFic that has been written to alter or 'fix' the original works.
Usually it concerns things in a certain book/film/series etc that didn't work or the author didnt want to happen.
Alot of Torchwood enthusiasts have recently been doing this with the 3rd series - Children of Earth. To avoid/change certain events that happened, most likely in episodes 4 and 5.
Alot of debate has gone on concerning the writings for this series and the uproar suggests more of a fix-fic rather than fan-fic.