Online retailing giant Amazon.com suffered a rare service outage on Monday, with the site going dark for about 30 minutes. Based on the firm’s 2012 net sales, the outage cost Amazon nearly $2 million, or over $66,000 per minute offline.

(The back of the napkin calculations are courtesy of Kelly Clay of Forbes.)

Amazon hasn’t issued a statement about the outage, but the firm’s Amazon Web Services health dashboard indicates it affected AWS as well. Such an outage is rare for Amazon, but it was the third in series of strange online services outages this past week.

As you might recall, Microsoft’s Outlook.com was offline for a few hours last week, and longer for some mobile users. And all Google services experienced an 11-minute outage Friday as well. One histrionic report noted that this outage impacted 40 percent of all Internet traffic.

Sun spots? Terrorism? The conspiracy theorists are sure to savor the possibilities. But it’s perhaps most interesting that these types of outages aren’t more common. Amazon, Google, and Microsoft each serve many millions of customers and have global reach.

And of course, the cloud computing doubters—who, like global warming doubters, are increasingly at odds with reality—will argue that such outages prove that our move away from on-premises hardware and local storage is nothing but a temporary trend. But it is ironic that the temporary outage of one online service sends users to another—Twitter or Facebook, perhaps—to complain. Perhaps we should take these moments as a sign that it’s time to disconnect, if only for a short while.

Related: "Amazon Web Services Adds Windows Support"