All very good suggestions so far.
- try the original Buffalo wings at the Anchor Bar in Buffalo
- if you like boxing, the International Boxing Hall of Fame is in Canastota, NY
It is not a patch on Cooperstown but if you like boxing, you will like it. (I got to meet a former world champion on an induction weekend)
- I've biked the Erie Canal as well. If you like that sort of thing, rent a bike and do a section. It is picturesque.
- the Fenimore museum in Cooperstown is good as well, if you are stopping there anyway. Also, avoid Cooperstown at all costs when they have their induction weekends. It is a madhouse.
- the Finger Lakes area is really nice too. We have spent a couple of really nice long summer weekends tooling around Ithaca, at Cornell, etc..