Back to NH

So I am officially booked on a plane to New Hampshire for another round of training. I have come to really enjoy the North East, but something tells me that this time it's going to be very different.  This is due to the fact that I will be flying out on December 13th.  That's right; heading up to New England in the dead of winter.  Luckily, here is the rental car that I have booked:

Aside from staying warm and not trashing the rental, anyone got any ideas on what I should do while in the Nashua/Boston area?  Don't say Cheers, because I did that already.