As Bitcoin becomes an increasingly popular form of digital cash, the cryptocurrency is being accepted in exchange for everything from socks to sushi to heroin. If one anarchist has his way, it’ll soon be used to buy murder, too.Last month I received an encrypted email from someone calling himself by the pseudonym Kuwabatake Sanjuro, who pointed me towards his recent creation: The website Assassination Market, a crowdfunding service that lets anyone anonymously contribute bitcoins towards a bounty on the head of any government official–a kind of Kickstarter for political assassinations. According to Assassination Market’s rules, if someone on