I haven't seen a large foraging flock, however recently (September) on the edge of Lake Ontario there was a roost of about 20 crows resting in some trees overlooking the lake to one side and a field of goldenrod/marsh to the other. It was late afternoon and the weather was quite solemn but beautifully peaceful. They were totally silent and resting.
As for other birds in large flocks - murmurations of starlings or foraging on lawns, ring billed gulls, Canada geese, and a flock of 12 vultures flew over my neighbourhood late summer.