As Firefox pops the champagne on its fifth birthday, one of its founding fathers has warned the world against an interwebs ruled by a certain money-minded tech giant.

That would be Google.

The Mountain View Chocolate Factory was instrumental in the rise of Mozilla's open-source web browser, contributing not only code, but considerable amounts of cash. Since 2004, Mozilla has pocketed a slice of all Google search cash generated by Firefox traffic, and in 2006 and 2007, Mountain View dollars accounted for more than 85 per cent of the open-sourcers' revenues.

But following the debut of Google's very own Chrome browser last year, a certain chilliness has come between the two. Their financial relationship hasn't changed - Mozilla still needs the cash, and Google still needs the traffic - but in other ways, they aren't as close as they once were.

Firefox was founded to revive the mid-90s browser wars with Microsoft and Internet Explorer. But five years after the official debut of Firefox in November 2004, a kind of browser cold war has developed with Microsoft's biggest rival.

"I look at Google and I don't see a lot of alignment with the big picture of the internet," says Asa Dotzler, the ten-year Mozilla vet who was among the team of three or four who founded the Firefox project back in 2002.

"Google is essentially an advertising company. That's where they make their money. They provide a wonderful service - primarily their search service - but it serves their advertising goals. It serves their revenue goals. The more they can know about their users, the more effective they believe they can advertise, the more money they believe they can make. That is most fundamental."

He doesn't see Google as the new Microsoft. Far from it. But Google is still a threat to the Mozilla way. Redmond and Mountain View have absolutely nothing in common, Dotzler says, except that they're both public companies legally beholden to maximize revenue for their stockholders. He's adamant that if Google's ad-centric vision comes to dominate, the web will wind up as something we've all seen before.

"I hope that there is renewed competition in the search space and in the advertising space and in revenue models for the web beyond advertising," he says. "I fear that we would end up in a worse case scenario where the users of the web become consumers of content who sit in front of commercial advertising all day long and have no control over their experience. And that sounds like cable TV to me. The internet can be so much more."

The irony, of course, is that Google ads are still propping Mozilla's bottom line. But the organization has revenue deals with multiple search engines, and Dotzler insists that none of them - not even the most lucrative - has an effect on the company's egalitarian mindset.

As you might expect, he wholeheartedly nominates Mozilla as the outfit who can save the net from both Microsoft and Google. "Mozilla creates a product that makes sure that the non-commercial aspects of the web - those things which haven't purely been designed to generate revenue - are well represented and that anyone can come along and participate without having to be a part of the financial model of the web," he says.

"There are civic and cultural and educational aspects of the internet that needs a defender and an advocate. They won't get that from traditional commercial organizations who have a legal responsibility not to care about this stuff."