http://dealbook.nytimes.com/2013/12/21/into-the-bitcoin-mines/On the flat lava plain of Reykjanesbaer, Iceland, near the Arctic Circle, you can find the mines of Bitcoin.
To get there, you pass through a fortified gate and enter a featureless yellow building. After checking in with a guard behind bulletproof glass, you face four more security checkpoints, including a so-called man trap that allows passage only after the door behind you has shut. This brings you to the center of the operation, a fluorescent-lit room with more than 100 whirring silver computers, each in a locked cabinet and each cooled by blasts of Arctic air shot up from vents in the floor.
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At the end of each day, the spoils are divided up and sent to Cloud Hashing’s customers. Last Wednesday, for example, the entire operation unlocked 225 Bitcoins, valued at around $160,000 at recent prices. Cloud Hashing keeps about 20 percent of the capacity for its own mining.
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