There have been several posts directly related to downtime and issues coming from Sandy.

ie:

Fog Creek is about to go down: http://news.ycombinator.com/item?id=4717279

Internap evacuates LGA datacenter: http://news.ycombinator.com/item?id=4715889

Even a poll form PG, Should we push the YC deadline back by a day because of the storm?: http://news.ycombinator.com/item?id=4715829

How have you, your company, sites, etc been impacted by Sandy? Such as a service outage, loss of functionality, nothing, complete and utter destruction?