Sadly, I'm not sure Three Fellas in Marlborough belongs on the list anymore.
They tore down the gas station and separate building that housed a 7-Eleven (long closed before is got torn down) and the prior Three Fellas on the corner of North Main and Rte. 66. In it's place, there is a much larger gas station with a convenience store/coffee shop/restaurant that all share the same door. Three Fellas occupies the "restaurant" side of the building to the left.
The ambiance is decidedly different than when Three Fellas was in its own space. Gone is the hole-in-the-wall hidden gem character and replaced by an unremarkable florescent and cold metal vibe. It's still thin crust, but the slices seem smaller than I remember. Also, I don't know if they had the conveyer oven before the old building was torn down, but they do now and it is out in the open for all to see. Finally note is the awkward site of people coming out of a gas station with pizza boxes.