Bitcoin seems to be the currency of choice when it comes to demanding ransoms, and that is because culprits demanding payment can hide behind a pseudonym (Bitcoin itself is not actually anonymous). So it is no surprise that a hacking organization has instructed Apple to fork over a Bitcoin ransom in exchange for not leaking a cache of iCloud

Source: Hot Hardware – Hackers Threaten To Remote Wipe 300M iPhones Unless Apple Pays 71 Bitcoin Ransom