I bake, and I cook, that's really what gets me calm and relaxed, as I can't really stay angry when I am baking a cake, muffins, or cookies.
Another thing I do, is sit down with a pad and paper and just write out the first words that come to my mind, or, if it's someone who has made me unhappy, or hurt my feelings, I write a short note, then burn it, letting my negative feelings drift away like smoke.