Since you're coming from a bit farther away, I would really suggest a drive up the coast if you have the time. Portsmouth, NH and Portland, ME are great towns. Lots of history and very good food. Hampton will probably be dead by that time of year, which is only a bonus.
If you don't have time to go all the way up to Portland, drive over the bridge out of Portsmouth in to Kittery, ME and find yourself some lobster. I'd suggest Chauncey Creek Lobster Pier, for the kind of place where you're eating right on the water and can bring in anything they don't sell. Bonus that I haven't seen many tourists there (usually I'm the only one!). Local folks show up with a lot of beer and tend to just eat and drink for a few hours there.
My wife and I are headed for 3 day weekends to Portland in Sept and Portsmouth in Oct, if that's any clue to how much we like the area.