You don't need to be a Sidekick owner on Deutsche Telekom's (NYSE:DT) T-Mobile to curse cloud computing, but it's a good place to start.

Microsoft's (NASDAQ:MSFT) Danger subsidiary has seriously blown it this month. It has apparently lost the server-stored data on T-Mobile's Sidekick phones that have been recently reset, had their batteries removed, or let their batteries drain out completely before a charge.

"We are thankful for your continued patience as Microsoft/Danger continues to work on preserving platform stability and restoring all services for our Sidekick customers," reads yesterday's T-Mobile announcement. "Regarding those of you who have lost personal content, T-Mobile and Microsoft/Danger continue to do all we can to recover and return any lost information."

Many Sidekick data customers are finding that the Microsoft-stored information on their phones -- contacts, snapshots, calendar entries, you name it -- is gone. T-Mobile indicates that some of the lost content may be recoverable, but it's prepared to offer up $100 in credit to those who suffer "significant and permanent" data loss.

There aren't a whole lot of Sidekick owners out there these days, but this has huge implications for those who generally believe that the cloud has their back.

Robin, Tonto, and lost data
This has happened before, of course. Data-backup specialist Carbonite suffered the embarrassment of failing a few of its customers last year, when its servers acted up. Network outages that result in permanent data loss happen, and it's time to assess how much faith we have in a third party's ability to maintain, back up, and eventually restore the information that computer users aren't storing on their ends.

Few people are talking about data-loss cases and their impact on the cloud-computing revolution, because these problems really haven't hit the big players yet. What do you think would happen if the 250 million-plus Yahoo! (NASDAQ:YHOO) email accounts had all of their virtual mail zapped? You know you haven't printed out or backed up every vital email that you've ever received.

What if it were Facebook or Twitter, with a year's worth of status updates and tweets? What if it were the novel you were nearly finished with on Google (NASDAQ:GOOG) Docs, or the digital photographs you deleted from your phone the moment you uploaded them to Flickr or American Greetings' (NYSE:AM) Webshots, where the tempting proposition on the landing page reads, "Camera full? Upload now."

There would be an uproar in any of these cases, but imagine if there were more than just effort and nostalgia at stake. What if premium cloud-computing platforms crashed with permanent consequences?

The entire premise behind salesforce.com (NYSE:CRM) is that it can provide customer-relationship management and other corporate apps in a cheaper and more portable manner than traditional computer-stored software solutions can. It's the poster child for cloud computing in the enterprise space. Meanwhile, Web-hosting giant Rackspace's (NYSE:RAX) fastest-growing business segment is serving up cloud-computing apps for its clients. Livelihoods are at stake for these premium providers, so you know they have backups in place in case of hardware failure, software corruption, viruses, or outright theft.

But customers were also paying up for T-Mobile data plans. We can no longer blindly trust all cloud-computing platforms.

The unlikely party pooper 
If there is any irony to the Sidekick fiasco, it's that Microsoft is to blame. On the surface, the world's leading software company stands to lose the most in the cloud revolution. Its Office suite of productivity programs is the industry standard, but cloud computing has birthed cheaper Web-based clones of Word, Excel, and PowerPoint.

And as more programs move to server-stored solutions, Internet connections will trump the spec sheets on user computers. Operating systems will become more interchangeable, and it won't be as necessary to upgrade PCs with a new version of Windows every few years.

So what's the deal with Mr. Softy? Could Microsoft be a cunning saboteur of the revolution that threatens to make it a mere mortal?

No. If anything, this will only hurt Microsoft as it seeks to market cloud-stored solutions in the future, so it can compete with its nimbler foes.

"Remember the Sidekick" will be the rallying cry of its competitors, especially if the data-recovery efforts fail and T-Mobile finds itself handing out a lot of $100 credits.

Computer users will be more skeptical as they go cloud-hopping in the future, but it's not as if they've never suffered data loss on their PC-stored files.

The revolution marches on, with sobering maturity.

Salesforce.com, Google, and Rackspace Hosting are Motley Fool Rule Breakers picks. Microsoft is a Motley Fool Inside Value recommendation. Try any of our Foolish newsletter services free for 30 days.

Longtime Fool contributor Rick Munarriz believes that every cloud-computing snafu has a silver lining. He owns no shares in any of the companies in this story. The Fool has a disclosure policy.