Reign in Hell, by
amanuensis1.
G. Ten-and-Rose.
Spoilers: Doomsday
A what-if from a particular moment in Doomsday. I like this for lots of reasons: the writing, because it's so very Doctor, because it's fresh and something I've not seen explored anywhere else, because I like to think of this for the Doctor and Rose, and because it just feels right.