My husband and I are escaping NYC for an urban-to-urban weekend in Boston. We'll be staying on Charles Street and wanted a recommendation for something fabulous in the area for Sat night (would be nice to be able to stroll there, rather than take a taxi). Preferably something non-ethnic, more local and greenmarket-y (I know -- not really the season). It doesn't have to be super fancy - but we don't mind paying for really great food. We love seafod -- esp. lobster rolls. Small places - lesser know with great food is fine, too. Any suggestions?