For many years in the hidden spaces of the Net, rumors have spread that cryptographic systems as we know them are worthless. Some claim that every cryptographic system out there has already been compromised because the National Security Agency only permits those systems that it has been able to tamper with in subtle ways to be published. Cryptographers they can't compromise, so the stories go, silently disappear and are never to be heard from again. More recently, advances in quantum computing have caused brand new stories to appear on forums and in IRC channels, with the requisite flame wars hot …