Gunstock has fireworks at midnight on New Years Eve.
I just got this in an email from them:
The entire mountain is open late for you to enjoy Skiing, Riding, Tubing, Snowshoeing Tours, Horse Drawn Wagon Rides and much more. Lifts are open for skiing and riding until 11:20pm.
1 hour of tubing. Take a Snow Shoe Hike. Horse Drawn Wagon Rides will be available from 7pm to 10pm. Live Music in the Main Lodge featuring the Nobody's Fault Band playing from 8pm to midnight.
The event ends at midnight with a fireworks show on the mountain.
Bring the whole family.
R2B