NYC to Du Bois and back again...

If you detour to State College PA (dead center of the state, approximately), which is about 20 minutes off of 80 -- 10 if you drive like me -- there are some cute places. The Tavern has some great German food but doesn't open until 5 PM, The Corner is famous for its grilled sticky buns, and Olde New York is great for German/Polish/generally Eastern European stuff.

If the weather were warmer and leaves were on the trees, I would recommend the http://en.wikipedia.org/wiki/Grand_Canyon_of_Pennsylvania.

I too suggest a stop in State College, PA. Stop in at the http://www.creamery.psu.edu/ on the Penn State campus if you're in the mood for ice cream. It's The Diner (not the Corner) that has the grilled sticky buns -- the Corner Room is also excellent food. http://www.herwigsaustrianbistro.com/has some great food too if you want something German-like; it's Austrian (all of these restaurants are along the same stretch of road in the downtown area; College Ave).

http://www.martinguitar.com/visit/tour.html in Bethlehem (I'm pretty sure it's less than 30 minutes south of I-80) offers free factory tours.