For those who aren't aware, Fate/stay night (the visual novel) has been mentioned/recommended here before in Eliezer's Three Worlds Collide short story:

I suspect the aliens will consider this one of their great historical works of literature, like Hamlet or Fate/stay night -

Reading the visual novel can take some time, so anyone who isn't interested in that should really consider watching this TV adaption instead. Personally, I found Unlimited Blade Works to be the best part of Fate/stay night (closely followed by Heaven's Feel, which they've also promised to make a TV adaption of), so you wouldn't be missing too much in my opinion.