Roughly 150,000 Gmail users were left without access to their contacts and email and chat archives yesterday, Computerworld reports. Welcome to the world of cloud computing, investors. Run apps in the cloud, and you run the risk of losing data. Outages are part of life on the Web.

For years, (NYSE: CRM) battled the perception that outages would destroy its business. We now know that's not true, but the company has invested heavily -- more than $90 million over the last fiscal year alone -- to build out its data centers to ease frayed nerves. Google (Nasdaq: GOOG) faces similar expenses for fortifying Gmail and its entire Google Apps suite.

And that creates an opportunity for disruption. Knowing outages are unacceptable, corporations have long employed both local and remote data back-up options. What about a system for consumers that backs up data that exists in the cloud to a locally controlled hard disk or server?

Think of it as Dropbox or, only in reverse. I'd designate the local hard drive I'd want Google Apps or Meebo or QuickBooks Online or whatever to back up to and then synchronize automatically. Everything of mine in the cloud would simply save to a disk.

You can bet cloud-computing apps providers such as NetSuite (NYSE: N) and SuccessFactors (Nasdaq: SFSF) would love to see technology like this. At the very least, it could remove a key concern about using their services and at the same time reduce their need for investing in backup infrastructure.

If I know tech and developers -- and I've known more than my share -- a solution for this is either under development or already exists. Either way, some form of synchronization strikes me as an important link in the multibillion-dollar cloud computing value chain.

Do you agree? Disagree? Let us know what you think about Gmail, data storage stocks, and the cloud computing investment opportunity using the comment box below. You can also rate Google in Motley Fool CAPS.

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