the 'Fifty Plus Advocate' (whatever that is) has a list of some discount offers in New England for senior sliders. Look at the article for more information (and be sure to ask the ski area directly), but the summary is:

Ski Area 60+ 65+ 70+ 75+ 80+
Jiminy Peak Discount Discount Discount Discount
Berkshire East Discount Discount Discount Discount Free
Catamount Discount Discount Discount Discount Free
Otis Ridge Free Free Free
Gunstock Discount Discount Free Free Free
King Pine Discount Discount Bigger Discount Bigger Discount Free on non-holiday, mid-week, Biggest Discount weekends/holidays
Loon Free
Cochran's Free (72+) Free Free
Killington Discount Discount Discount Free
Pico Discount Discount Discount Free
Mount Snow Discount Discount Discount Discount
Jay Peak Discount Discount Discount Discount
Sunday River Discount Discount Discount Nearly free
Sugarloaf Discount Discount Discount Nearly free

My friend has a life goal of being able to ski for free and use the parking reserved for 80+ skiers. I wish him well.