Digital currency Bitcoin has grown sensationally, with 11 million Bitcoins worth nearly $2 billion in circulation. It's the ultimate Internet-age currency: Bitcoin circulates only online, trades anonymously and isn't regulated by any government. - 

So far, 2014 has not been a good year for Bitcoin. The crypto-currency's price has been extremely volatile, one of its most important exchanges has had major software issues, and just the other day $2.5 million worth of the virtual cash was hacked from a new online black market for drugs called Silk Road 2.0.

All of the bad news has had many people asking whether this is the end for the new form of online cash. Advocates say this is just growing pains, but critics say it reveals deeper problems.

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