Soy sauce seems to make its way into all of Japanese cuisine one way or another. Often times just as a replacement for salt in cooking. I find that my bottle in my apartment most commonly makes its way into soups. I usually boil green onions and other stuff like a chicken carcass or fish flakes, and adding a couple spoonfuls of soy sauce really brings out the rest of the flavors in the broth. I can then use the broth for some miso soup, a soba noodle base, or even add some curry blocks to turn the whole concoction into a thick curry to eat with rice.