On Feb. 14, 2006, many Google e-mail users received an unexpected Valentine’s Day present. When they logged in to their accounts, there it was: instant messaging, fully integrated with their e-mail system. Gmail users could now chat in the same browser window as their inbox. Just as with e-mail, the system would save a transcript of every chat and, better yet, the text of archived transcripts would be searchable. There was nothing to download, nothing to install.

It was technology magic.

This was another overnight success for Google, the company most everybody loves (with the exception of a few countries, some municipal governments, and a host of proto-competitors such as Microsoft, IBM and Yahoo). Over the past few years, Google has released a series of Web-based applications that have raised the bar for its competitors, just as its search engine did when it burst onto the scene at the end of 1999. When Gmail debuted on April 1, 2004, for example, it gave users a gigabyte of storage—10 times as much as Yahoo and Microsoft’s free e-mail services.

Google releases its products with little fanfare, labeling them beta versions and leaving them that way for years. Yet its desktop search, map, e-mail and other services are among the world’s best and most popular applications. And whether you know it or not, your employees are probably using them.

But Google is not just a search company, or an applications company. A company that can scan billions of webpages for a handful of words in less than a second (a search for "CIO magazine" returned almost 28 million results, prioritized by relevance, in 0.14 seconds) deserves to be acknowledged for what it really is: a supercomputer.

"What Google recognized was that if they built their own system using cheap, off-the-shelf PCs and ran their own operating system"—the Google File System, a highly customized version of Linux—"they could afford limitless expansion," says Chris Sherman, executive editor of Searchenginewatch.com. In order to build the best search engine possible, Google connected thousands, then tens of thousands, of servers. And at some point that infrastructure and the possibilities it afforded became the company’s primary focus. What followed was a series of services that took advantage of Google’s ability to process transactions at a speed and scale never before achieved. And these Web-based services don’t require users to download a thing. Google provides the computing power. All you need is a browser.

"What Google has that’s extraordinary is not search but the highly optimized computing platform," says Sue Feldman, VP of content technologies research at IDC (a sister company to CIO’s publisher). That platform has Google poised to lead the Web computing revolution that everyone in the IT industry has been talking about since the 1990s.