It whirled around, and she had another snowball ready to hit it in the rump.

NEWYORKER: Amundsen

Banks failing and subsequent counterparty defaults which in turn result in another bank to fail and the snowball rolls down the mountain getting larger and larger with greater and greater force.

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Rumors snowball, people will take all their money out on a whim and put it back in again on another whim, and that's really what we've been seeing the last few days.

NPR: Taking Stock of China's Chaotic Market