The size of Google’s secret computing complex in Oregon – as big as two football fields – sheds light on only a fraction of the company’s ambitions.

The three big internet companies – Google, Yahoo! and Microsoft – are locked in a battle that will shape our behaviour for decades to come. The key to victory is how information – ranging from the addresses of local restaurants to television schedules to sophisticated data on, say, the workings of the world’s stock markets – is handled and distributed. This will be the overarching problem the PhDs (Google has for some time been engaged in a global recruiting drive, seeking out only the very brightest) who work in the Oregon "Googleplex" will be working on.

Google recently hinted at the scale of the task when Eric Schmidt, the company’s chief executive, revealed its own analysts have worked out that it would take 300 years to make all the world’s information searchable.

Google, Yahoo and Microsoft are all working on the premise that if information can be searched it can – in Silicon Valley jargon – be "monetised". So far, this has meant that adverts can be attached to it.

Google makes the lion’s share of its revenues – the company's sales came in at more than $2 billion in the first three months of this year – by adding ads to search results on its flagship google.com website. But it is worried that these revenues will eventually – and inevitably – slow. To counter this it is using its vast $10 billion cash pile in a breakneck drive to diversify.

Among other things, the company also wants to be a television station (Google Video), a telephone company (GoogleTalk), a classified ads site (Google Base) and an online retailer (Froogle). Yahoo and Microsoft have ambitions along the same lines.

Among the seemingly more outlandish ideas seriously considered by Google have been the construction of a "space elevator" – a massive conveyor belt that would take payloads into space.

But Google’s competitors will be far more worried – for the time being – about its ambitions closer to home. In particular, Microsoft, the world’s largest software developer, is under threat after Google recently added to its suite of software products by revealing a spreadsheet program, a rival to Microsoft’s market leading Excel, and a word-processing package, Writely, designed to wean users off Microsoft’s near ubiquitous Word.

This new generation of "web-based applications" use huge "server farms" – massive clusters of machines that can harness far more computing power to solve a problem than a single PC can. These farms – the Oregan site is almost certainly home to one – are used to store and process data and a user's PC effectively becomes a dumb terminal, used to access the supercomputer "brain" through the web.

Google has also been busy entering markets by proxy. It is the source of a massive amount of funding for the Mozilla Foundation, which makes the Firefox internet browser – the main rival to Microsoft’s Internet Explorer. Mozilla is an open "source company" – which means it shares the blueprints – or "source code" of its products with anybody who wants them.

Microsoft regards these sort of companies as public enemy No 1. It is hard not to see Google’s activity as calculated to irk Bill Gates, Microsoft’s chairman, the world’s richest man. The ploy has probably worked – Microsoft’s share price plunged earlier this year after it said it would spend $2 billion in an effort to keep up with Google.

There are even suggestions that Google wants to build its own version of the internet. Already the company has offered to make San Francisco into one giant "hotspot" – where people with a wireless connection can access the web for free. But it has also advertised for experts in "dark fibre" – the thousands of miles of optical cable that were laid at the height of the dot-com boom but which have since gone unused. It could conceivably use these as a kind of super-internet, capable of transmitting much more information at much higher speeds than currently possible on the web. The Oregan site could play a key role in such a project by allowing Google to host vast amounts of data there.

Taking all these projects - just a taste of Google's portfolio - in aggregate, a picture forms where one day in the future Google will not only help you find stuff on the web – for free. It will also bill you for using its voice and data network (a senior BT executive last week identified Google as the major threat to his company). You will not even need to visit Amazon.com to buy a book, since the entire canon will be available online through Google Print, the controversial plan to digitise the world’s great libraries. If you get lost away from your PC, Google Maps will help you find your way – probably through your mobile phone, a gadget on which Google has its sights firmly set.

And if you need to urgently send a payload into space, there’s even a chance it will be able to help you there as well.

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