Google has nabbed some huge customers for its most important new business - cloud computing

Google wants to become the biggest thing in a hot young market called cloud computing, where companies rent computers and storage over the internet instead of buying that equipment themselves.

Businesses have fallen in love with cloud computing. It gives them access to unlimited computing power at a marginal cost, without having to actually manage all the hardware, software, and networks.

That's why companies will spend $127 billion by 2018 on public cloud computing services, according to IDC.

Right now, Amazon is the market leader, credited with inventing the market and offering the biggest, baddest cloud of them all. In April, Amazon revealed its cloud computing unit was on track to be a $6 billion business with $1 billion in profit this year.

Google, who runs some of the world's most sophisticated data centers, is pushing hard to unseat Amazon. So is Microsoft. And IBM. And Oracle. And Cisco. And Rackspace. And every other big IT company that targets businesses.

While Google has the technical chops to beat Amazon (even though its cloud doesn't yet offer the enormous plethora of services available on Amazon's cloud), it has been lacking one important thing: Customers to trot out as examples.

Google had a few marque customers that it could discuss including Snapchat, Khan Academy, and Rovio, but those weren't the kind of huge Fortune 500 examples it needs to convince mainstream businesses to try its cloud over Microsoft or IBM - vendors these companies have been working with for years.

This month, that changed.

At the Google Next event held in San Francisco on Tuesday, Google showcased testimonials from some huge enterprise companies, according to a report from Wall Street analyst Colin Sebastian from Baird Equity Research.

These new customers are:

• PricewaterhouseCoopers (who has become a big partner, also using and reselling Google Apps)
• SunGard Financial Systems
• JDA Software
• General Mills
• Coca Cola
• HTC
• Best Buy

Google also claims its cloud now hosts "over 4 million applications."

The man responsible for building all the tech that runs Google, including its cloud, Urs Hölzle, has some big audacious goals for Google's cloud. He recently told Business Insider:

"Five years from now, my goal is that all the CIOs of the Citibanks of the world are GCP [Google Cloud Compute] customers. Not because they were forced to but because they realize it's far better than doing it themselves. ... We have financial customers - they are some of the eager adopters."

Google is taking its big customer-testimonial on the road, too, to try and convince more enterprises to try Google's cloud. The "Google Next" event has already hit New York and San Francisco. Next up is Tokyo, London, Amsterdam, and more cities will be announced soon.