Chp 41 of Harry Potter & The Methods of Rationality by Less Wrong.[link]
Draco caught Hermione when she fall off the Hogwarts roof during Battle Magic. Hermione urged Draco to let her go so Draco can resume his battle with General Potter. Draco was torn between letting her go or not. And the result... well you have to read the fanfic!^^
From this chapter Draco got the nickname 'Draco, The Drop Lord'.