Running out-of-date software is risky if you value security, but running outdated bitcoin software can create invalid currency. Many bitcoin wallets using outdated software are currently vulnerable to double-spending of confirmed transactions, a bitcoin warning states. A bitcoin-savvy gambler exploited the random number generation system at the online bitcoin gambling site Primedice to win about $1 million. A hacker then exploited the patched fix to win over 2,000 more bitcoins. In Greece, Greeks are turning to cryptocurrency to transfer their money out of the country.”]