If you have access to a pool try deep water running. You can find program ideas with google and I think Pete Pfitzinger has written some stuff with this idea. Basic stuff includes using a flotation belt to keep your stride as close to normal as possible, doing 'speed' reps and you can even add slightly different strides to imitate track drills. Every little bit helps. My favorite story is Joan Benoit Samuelson using pool running to prep for her first Olympic trial after knee surgery, winning it and the gold medal.
When you do get to Boston be sure to sit through some of the guest speakers they have. You will get to hear really great people tell their stories.