Cory Doctorow (of Boing Boing fame) wrote a sci-fi novelette about a datacenter during a crisis: http://craphound.com/overclocked/Cory_Doctorow_-_Overclocked...

I personally didn't find this piece particularly great, but there's an entry in the genre for you.

What makes it even more exciting is that some of the companies were a bank and a hospital. Lesson learned - a bank gets far more anxious than a hospital when their servers go down.

I'm pretty sure there were Zombies roaming the aisles of servers where the power was out, that might help the box office sales.