[0xbxd]

That's not how quantum computers work. They ("quantum networking") significantly increase security as you can tell whether a qubit has already been observed (eavesdropped) or not. Also, there are proven asymmetric cryptographic algorithms that work with quantum computers. Algorithms based on factorization (RSA) won't be safe any more but you still need a large amount of qubits (around 1000s - don't cite me on this please) to break them, which has not been achieved yet.

Definitely not the end of the world.

edit:// And they can not solve any NP-complete problem in polynomial time. That is a common misconception and not based on facts.

edit2:// Researchers working on quantum computers actually don't believe that they will make it mainstream (partially due to their complexity like cooling them down to near zero Kelvin) but instead be specialized systems available via the internet for rent - or something similar. More on the side of predicting complex systems like the weather than powering your smartphone. Then again, who thought the PC would make it mainstream.