Google’s expansive ambitions have finally been given concrete expression - in the shape of a secret giant computing complex, the size of two football fields, on the banks of the Columbia River in Oregon.

The vast plant is thought to be the site of a massive super-computer and data storage centre. It is likely to play a major part in Google’s plans to dominate the way in which the world’s information is ordered, stored and distributed.

In particular, the site appears to signal how Google intends to exploit huge "server farms" - massive clusters of machines that can harness far more computing power to solve a problem than a single PC can.

Such large infrastructure plants are often kept secret because of security concerns.

A new generation of "web-based applications" such as Google's recently released spreadsheet and word-processing programs use these farms to store and process data. A user's PC effectively becomes a dumb terminal, used to access the supercomputer "brain" through the web.

Significantly, the Oregon site is also well-served by fibre-optics networks. Google has placed adverts looking for experts in so-called "dark fibre" – optical networks laid at the height of the dot-com boom, which have since gone unused.

Analysts have speculated that such infrastructure could be used by Google to build its own alternative to the public net, where information could be transmitted far faster than on the conventional web.

Google executives have so far refused to comment on the plant, pictured in the New York Times today, signalling the deep-rooted culture of secrecy that exists in a group where employees are encouraged to work on their own undercover projects on the company’s time.

However, it is known that Google is currently engaged in a breakneck drive to diversify. It dominates the market for online search – and the closely linked advertising sector, but is aware that it cannot rely on revenues from these areas to grow indefinitely.

To prepare for the day when advertising dollars start to slow, Google has tapped its $10 billion cash pile to enter into field such as internet telephony (through Google Talk), retailing (Froogle) and online television (Google Video).

A data distribution business, built on optical technology, could complement such a portfolio.

However, Google faces fierce competition. Microsoft and Yahoo, Google’s chief rivals are both building similar large sites upstream from the "Googleplex".

Do you have a view on Google's expansion plans, or the future of the web? Have your say here.

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