Not the metaphor I'd use . . .
Stephen Wolfram's Alpha

"Google uncloaks once-secret server"

Google reveals a little more of how they do it. (CNet News, 4/1.)

Google's big surprise: each server has its own 12-volt battery to supply power if there's a problem with the main source of electricity. The company also revealed for the first time that since 2005, its data centers have been composed of standard shipping containers--each with 1,160 servers and a power consumption that can reach 250 kilowatts.