I know that there was just a "best sandwich in Boston" thread, but that's not really what I'm looking for.
I'm looking more for a sandwich DESTINATION: a place that serves not one great sandwich, but numerous fantastic (and, preferably, inventive) sandwich options. A real professional sandwich establishment. And I don't care if it's in Boston -- I'm willing to travel for this one, to pretty much anywhere in the greater (and I mean greater) Boston/Eastern Mass area.
Anyone have any places that fit the bill? It doesn't have to have JUST sandwiches, but multiple great offerings are key. Thanks!