Now THAT’S an entrance!…

manfromplanetx 's inclusion of The Postman Always Rings Twice and gunshotwound 's of Suddenly, Last Summer are examples not only of memorable entrances, but of cinematic symmetry in their exits:

TPART: the dropped lipstick.

SLS: the voice is heard before the descending elevator brings her into view; as the elevator ascends at the end, the voice is heard after she disappears.

I know there are other examples of characters who went out the way they came in (even if I can't think of them at the moment), but these are two of the nicest.