A quick search on www.kayak.com shows that JetBlue also flies PIT-BOS non stop for $69 each way (OK, I had to go to www.jetblue.com to find the one way price). I would recommend calling JetBlue/US Air to see if they offer any discounts for your situation. I have heard of some airlines offering prepaid passes although not in the lower 48. You may want to search both forums to see if you come up with anything and post there if you don't.