In 1965, Intel co-founder Gordon E. Moore published a paper in which he noted that, since it's invention in 1958, the number of components contained within integrated circuits had doubled every year; a trend which he predicted would continue for another 10. Now known as, Moore's law, this trend has in fact continued to this day, with computers doubling their processing power around once every 18 months. But there is a limit to just how long Moore's prediction can hold true, and many now predict that Moore's law will collapse sometime within the next 20 years or so. When it does, there will need to be a new technology waiting in line to take the place of the silicon processor. One likely candidate for a replacement, is the quantum computer.
Unlike digital processors, which are limited to a two state, binary value system of ones and zeros, quantum processors perform their computations by measuring the position, or spin, of individual atoms and interpreting that position as a value or “qubit”. This means, that because atoms can exist in a state of superposition, multiple states simultaneously, a single quantum processor could potentially possess the ability to perform millions of tasks at a time, as oppose to the single task to which modern processors are limited. Which isn't to say that this type of system is not without it's own set of problems and limitations, such as the current need to hold the superconductors within these systems at a temperature near absolute zero, or the fact that the processors themselves are highly susceptibility to interference from everything from simple sound vibrations to cosmic waves.
Despite these limitations, just last week the age of quantum computing moved one step closer to becoming a practical reality when Lockheed Martin became the proud owner of the world’s first first commercially sold quantum computer. This system, known as D-Wave One, uses a superconducting 128-qubit chip called Rainier, has an approximate footprint of about 100 feet, a power requirement of 15 kilowatts and, along with maintenance and tech-support of course, cost the company a rumored 10-million dollars. While the cost, and other obvious impracticalities of Lockheed's new toy make it unlikely that any of us will be surfing the net on a D-Wave of our own anytime in the near future, the system's mere existence is still a potentially important step on the way to making quantum computing a part of everyday reality.
If you'd like to try and wade a little deeper into the world of quantum computers on your own, THIS ARTICLE from How Stuff Works has one of the simpler explanations of the processor's inner working I was able to find. Or, if you'd really like to dive into the deep end of the pool, you should check out the following video from UNSW TV.