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Don't worry, you may never have to fix one of these. One of the predictions of Quantum Mechanics is that sub-atomic particles can effectively be in more than one state at a time. In theory, you should be able to use this property to build a computer that explores many possible solutions to a problem simultaneously rather than trying them one by one, as a normal computer would. This could be really neat for cracking cryptographic codes, or working out the shortest route by which you could visit all the pubs in your neighbourhood. But don't hold your breath: the best a quantum computer has manged so far is to factorise 33 into 3 times 11.