With its strong citrusy aroma and light lemon flavor, lemongrass is a cook's friend in dishes beyond the curries with which it's most associated. I like to process it to a paste with garlic, black pepper, and salt or fish sauce, and then rub the paste onto flank steak or chicken before grilling for great flavor.
I find it especially useful in making chicken broth, or even when I have a ready-made soup broth and want to make it more interesting. I use it whole, like a bay leaf, and it's hard to believe what an enlivening difference it makes, adding a sublime fragrance. I've come to think of it as my secret ingredient.
Look for lemongrass that feels firm at the bulb end, even if the upper stalk is dried out. Store it in the refrigerator, loosely wrapped in plastic. It will keep for a week or more, gradually losing flavor as it dries. Keep in mind that the flavor is only in the bulb end—the bottom few inches. Follow the prep instructions in the recipe to release the most flavor.