"Gmail Man" is the single greatest Microsoft ad ever made, but it isn't even an ad. Rather, it's a humorous internal video—aimed at Microsoft's own sales people—that positions its Office 365 service as a better alternative to Google's Gmail. The rationale is simple: Google reads every single email message that passes through Gmail and then generates context-sensitive ads that appear in the Gmail web client. This policy is at best suspicious, the Microsoft video implies (with great humor).

"He's everywhere and nowhere at the same time," the video says in a sing-song fashion as a humorous-looking character, Gmail Man, appears onscreen in an outfit reminiscent of a postal worker. "He peeks at every subject in un-real time. Probing every sentence and all your punctuation. Got his nose in every colon and every situation. He's the Gmail Man!"

As first reported by ZD's Mary Jo Foley, "Gmail Man" wasn't made for the public. It's an internal Microsoft video that aired during the Microsoft Global Exchange sales conference a week earlier. And while some may have trouble believing this wasn't leaked purposefully, Microsoft actually required the 12,000 Microsoft employees who attended the show to maintain strict silence over Twitter and other online routes. And until this video leaked, they did so about all the content discussed at the conference.

"Gmail Man" is effective because its basic premise is true: Google does read every email message that passes through Gmail, though the online giant will point out that this is done anonymously and that no human beings ever directly read the messages themselves. But as Windows Server expert Mark Minasi is fond of pointing out, you can use your powers for good or for evil. And Google's email scanning is not only done for good reasons, like scam detection. It's done to further Google's single financial success: advertising.

Some have accused Microsoft of "FUD" (fear, uncertainty, and doubt), a term that's used to purposefully diminish and dismiss something that its accusers feel is unworthy of debate. But "Gmail Man" is not FUD. In fact, as noted above, it's both effective and funny, because it rings true. And in the tradition of comedy being defined as "tragedy plus time," my years of experience with Gmail's terrible contextual ads explain why this video resonates with so many people, and for such a good reason: There's always been something suspicious about the advertising in Gmail and about Google's approach to privacy in general.

"Hey mailman!" a little girl asks Gmail Man in the video, astonished. "Are you looking at our mail?"

"No, heh heh heh," he answers. "I'm looking at everyone's mail."

Those who don't trust Microsoft will also point out that Gmail is free, whereas Microsoft's Office 365 is a paid service that costs at least $6 per user per month. And that the paid version of Gmail—Google Apps, which costs $5 per user month—has the ads disabled by default. (Amazingly, you can turn on the ads in the paid version too.) And that's true enough. But Microsoft's argument, of course, is that users should pay for Office 365 specifically because there are no ads, and that Microsoft isn't reading your email, as Google does, to generate its only real source of revenues.

Too, some have questioned why the "Gmail Man" video doesn't mention Hotmail, Microsoft's free and ad-based email service. But the reason is as simple as it is non-nefarious: Although Hotmail does display ads, those ads are not contextual—that is, the service isn't reading your email to generate ads—and have nothing to do with the content of your personal or work-related email messages. And since this video was aimed at internal sales people, it obviously targets a Microsoft product, Office 365, which they can sell to customers.

To the crowd that will never trust Microsoft, these basic arguments are met with the virtual version of fingers stuck in ears. They're just not listening. But I see this video and I wonder why Microsoft doesn't show a version of this on TV, in ads for Office 365. It's exactly the type of good-natured and effective competitive attack that Microsoft doesn't seem to have the stomach for these days. And it's sorely needed in a world in which the technology discussion is often dominated solely by Microsoft's rivals and those companies' fans.

Call it FUD all you want, Microsoft haters, but you're wrong. And Microsoft should seriously consider taking this message to the people. Internal videos are fine, and I'm sure this riled up the Microsoft sales people nicely. But it's time for the software giant to compete more aggressively. "Gmail Man" would be a great start.