Last week, on April Fool's Day, a jocular press release turned the buzz from Google's impending IPO to its new email service, to be called Gmail. Fellow Fool Alyce Lomax was pretty excited about the service's biggest selling point, a full gigabyte of storage space for Gmailers, so they "never have to delete." My first reaction was to wonder how many ads for male enhancement will fit in a gig of storage.

But I doubt that Yahoo! (NASDAQ:YHOO) and Microsoft (NASDAQ:MSFT), providers of the Web's most popular free email, were so nonchalant. After all, Google came out of nowhere to beat them at the search game, and the privately held upstart seems to strike gold with each new Internet venture.

But those two firms may find a little something to snicker at in today's headlines. Gmail is already under fire for the way it will read users' email. A story on the Associated Press wire quotes a variety of privacy advocates who are creeped out by Google's terms of service -- even though the service has yet to launch.

One worry: Copies of email will remain on the system even if deleted or after account termination. Another cause for creeps: computerized snooping.

Remember those advertisements that floated in the streets of Minority Report and served up personalized pitches after a retina scan? Gmail's snooping system will work a bit like that. It will read the displayed email, then dish out advertisements based on the content of the message. If you're talking recipes with Aunt Sue, expect to see ads hawking pots, pans, barbecue sauce, cookbooks, or -- if the software has a sense of humor -- fire extinguishers.

Potential users may be assuaged by Google's promise in its Gmail privacy policy that "No human reads your mail to target ads or other information without your consent," but that's not good enough for me. As companies like eBay (NASDAQ:EBAY) know, consumer information itself is a very valuable resource. And given the policy of hanging on to email even after it's been deleted -- for data mining, I assume -- we see that, in the end, that gig of storage isn't actually free. If you sign up for Gmail, you'll be paying for it with a chunk of your privacy, and, to my mind, a little bit of your soul.

Get the skinny on electronic issues in the Fool's Help with this STUPID computer! discussion board.

Fool contributor Seth Jayson is an occasional privacy advocate who is working on a backyard bunker. He owns no stake in any firm mentioned above. View his Fool profile here.