In a nutshell The Cold Equations is a story where a girl has stowed away on a shuttle: the flight is weight-critical, there isn't enough fuel, and she has to be jettisoned out of the airlock by the sympathetic pilot or the shuttle will crash. Science trumps sentiment. If all inhabitants of any given space ship represent aspects of the human personality (and I kind of think they do) then cold science ejects softness and warmth. The circumstances have been minutely engineered in advance to 'make' maths beat emotion.
For B7 fans this story has a special place as the inspiration for the episode 'Orbit', where the protagonists are Avon and Vila. In keeping with the B7 world-picture, neither of the protagonists has any more right or need to survive than the other, and the outcome initially seems to be dependent on brute force (Avon goes hunting for Vila with a gun) and is then resolved by intellect (Avon works out that there's a heavy thing he can throw out of the shuttle instead). According to the space-ship-as-personality theory Orbit is about what aspects of your personality you are willing to kill off, just in order to survive. And is it worth it? And if you find you don't need to kill your softness, how much have you damaged yourself, just by considering it?
An almost unbearable poignant additional note is that Michael Keating, who played Vila, tells us that the shots that show Vila crying alone in hiding represent Vila - the 'soft' half of the equation - trying to find the courage to give himself up to be killed.
I think the contrast between two ways of handling the same basic premise demonstrates a few interesting ideas: SF as metaphor (of course) and specifically space-ship-crew as metaphor-for-the-soul. How the same premise can be worked up in two completely different ways. How a writer engineers his stories to demonstrate a particular dynamic which rings very true to him.
The slashers answer to the Cold Equations, of course, is to lose weight by taking all their clothes off and throw them out the airlock. Incidentally I wrote a fan fiction of Orbit/The Cold equations called 'Digitally remastered' (which I think is a great title in context) which I think ends horribly but I forget. I might see if I can dig that up and improve on it.