I absolutely love psychoacoustics, it is the very reason I fell in love with sound to begin with, but frankly this is a very very hard question to answer. Psychoacoustics are rarely something really tangible like a sound or a certain technique. There are some cases where you can seriously point a finger at it, like the deep sine-wave in Irrèversible, the fading street-amb in Se7en, or, to give a personal reference, a distorted very high frequency tone I just used in a horror movie. But most of these things mustn't bear the entire scene by itself. It's partly because you can never tell how the systems will react to such extreme signals unless you actually do the mixing at the theater, it might be so quiet it makes no difference, but it might as well be so loud people forget the play altogether and just wanna hurt the one responsible. Everything drawing the audience from the action is seriously bad.
Every sound designer has his or her own little tricks and preferences, but mine is very often based in dissonance and insecurity, at least when doing horror, dystopian fiction and action (doing the same thing to a comedy may or may not render it into a tragedy/travesty instead, potentially effing it up completely). It all comes down to context: take a dripping pipe. In a cellar, it will make the owner virtually soil him/herself with anxiety, and give the audience a feeling of discomfort. In the desert, it's the most wonderful thing anyone possibly could imagine, next to a full stream, of course.
All this might very well give you nothing, but I do hope you understand what I meant by this. These things can't be made by the numbers, it HAS to be made by understanding what you wanna accomplish and what makes you tick yourself. Psychoacoustics is exactly what it's named after, based entirely in psychology, but by just listening to your inner voice and trusting your own judgment, you're already halfway there :-)