I live just south of you. This summer we drove to JFK, stayed overnight, and flew direct for less than it would cost to fly out of Boston. It certainly made the return trip less stressful as we didn't have to scramble through customs and recheck bags.
Last March we too drove to JKF for fa $400 rt light to SXM. Piece of cake driving day before and staying over; however, I don't think I'd try it in January or February with seasonable weather. This coming March we are scheduled on direct flight from Boston.
