It's time for a tax on e-mail. Taxes generally are not popular, but a tax on e-mail should prove to be a rare tax that most people support.

Few people would object to a tax that cost them pennies a day, at most, but would result in a reduction in some of the most tedious work they do each day — deleting junk e-mails.

Unlike most proposed taxes, a tax on e-mail is not primarily intended to raise money, though it would. The primary purpose of the tax would be to reduce junk mail or spam by imposing some costs on those who send out millions of unwanted e-mails a day, hawking cheap Viagra, get-rich-quick schemes, fake Rolex watches, male-enhancement products, cheaper medicines from Canada, or millions of dollars from a desperate Nigerian widow.

In the nondigital world, junk mail costs money to produce and deliver. The unwanted-mail items in the mailboxes at our homes cost money to print and for postage. Any business hoping to make money from a mass-mailing in the real world has to weigh the costs of printing and delivery against the likelihood of income from new sales.

Imagine if it cost nothing to print or deliver junk mail. The mailboxes at the end of our driveways or on our houses would be overflowing with unwanted material, obscuring the few pieces of legitimate mail — just like the digital mailboxes on our computers at home or work are overflowing with junk e-mail and spam.

A small tax on sending e-mail, a penny or less per e-mail, would cost the average person a few cents a day. But an Internet spamming operation or junk-mail producer sending out millions of e-mails a day would have to weigh the tax cost of tens of thousands of dollars against the probability of new revenue.

By imposing some costs on spammers, many would be forced to quit sending junk mail to millions of e-mail accounts.

And based on several estimates, about 90 percent of Internet traffic is junk mail. Clearly, there is a need to do something to reduce or stop junk mail.

The cost in terms of lost productivity in offices is very real.

It's also true that junk mail is not only a nuisance, but sometimes contains computer virus programs that can cause serious problems to home or office computers.

According to a recent article in the British magazine Prospect, it is estimated that 200 billion junk e-mails are sent daily around the world. More than 40 billion are believed to come from sources in the U.S. and Canada.

Imposing a cost on spammers to send junk e-mails would almost certainly cut down on spam and reduce the amount of time people spend cleaning the junk from their computer's e-mail system. And that would help businesses that must spend money for software and technology workers to help deal with incoming spam, and maintain spam- filtering software to prevent dangerous computer viruses from infiltrating and damaging company networks.

It's long past time for Internet service providers to be required to impose a small tax for each e-mail sent. Such a tax would have minimal impact on individual users, but would impose costs on junk mailers that would be large enough that most would be forced to stop. The revenue from such a tax could be dedicated to improving the nation's Internet infrastructure, expanding fiber-optic capabilities or bringing broadband service to rural areas.

An e-mail tax is one tax that would receive wide public support and would have an immediate positive impact on many people's lives.

The Obama administration should propose an e-mail tax, one that would have a negligible cost for most people and actually would be appreciated for its impact.