Use spent grains with care as feed. Because of the very high fibre content it is often recommended to mix them with two or three times their volume of feed grain, to prevent diarrhoea. If one has only two or three chooks you might not go through them that way before they get moldy.
They are also very high in protein, therefore in nitrogen, but not nearly so rich in other plant nutrients. As such they make a good fertiliser to fire up compost heaps or to use as is on salad plants, edible greens or grass. Scattering them on a lawn attracts a few birds. No worries, they don't stink that way.
Because of the nutrient imbalance heavy applications may discourage flowering and fruiting, but that depends on the plant and the soil. Out my window Moby Zucchini seems to be thriving and producing heavily in ground enriched by pale ales past. I have had poor yields of tomatoes that way.
