I have had, bar-none, the best pizza in the Naples area.  The thin crust, light smattering of toppings, and a drizzle of olive oil on top works best.  For soccer games, I've had pizza with salted potatoes on top.  At the port of Pozzuoli, I've had shellfish pizza replete with octopus, shrimp, and mussels. 

But by far the best and most unusual pizza I ate was in the town of Caserta about 15 miles North of Naples.  The restaurant served a white pizza (re: no tomato sauce) with melted smoked provolone cheese and a scattering of finely-grated walnuts.  De-licious!