Actually, a bunch of commercial quantum crypto systems were hacked a few years ago, in spite of being "theoretically unhackable". The details are at http://www.

Actually, a bunch of commercial quantum crypto systems were hacked a few years ago, in spite of being "theoretically unhackable". The details are at http://www.techrepublic.com/blog/security/quantum-hacking-cracks-quantum-crypto/4371 http://www.techrepublic.com/blog/security/quantum-hacking-cr..., but basically you can convince avalanche diodes that they're only receiving one photon by blinding them, and this lets you bypass the security inherent to the No-Cloning theorem and the Uncertainty Principle that quantum crypto relies on .