Everyone has an idea of what constitutes the perfect pillow: firm, soft, synthetic, or natural fillings. Whatever your preference, don.t settle on one until you.ve considered the full range of shapes and fillers, including giant body pillows or tube-shaped "cervical" pillows, designed to prevent stiff necks. And make sure you weigh the pros and cons of the full range of fillings, from microfoam to natural wool, feathers, cotton, kapok, or buckwheat.