Parmigiano-Reggiano, produced only in northern Italy's Emilia-Romagna region, is known as the king of Italian cheeses because it's sharp and sweet, with a crumbly texture and tiny crystals that give it a subtle crunch. It costs a princely sum, too, usually around $22 per pound. Pecorino Romano and Locatelli Pecorino Romano, which come from farther south, near Rome, are slightly saltier but still excellent grated, and they are less expensive (most run about $12 per pound). And if you're fine with topping your orecchiette with a non-Italian cheese, look for SarVecchio, from Wisconsin ($14 per pound).
Switch and save: $8 to $10 per pound