'Free Viagra! Click Here!!!!'

Your e-mail gets clogged with spam. Your conventional mail overflows with fliers, free offers and envelopes labeled "Dated Material! Open Immediately!"

Which bothers you more?

If you're like most people, you'll probably complain more about the spam. (If one more message offers you "Free Viagra!" you may smash the screen on which you're reading this.) A couple of mass-communication professors decided to figure out why.

Mariko Morimoto at the University of Georgia and Susan Chang at the University of Miami surveyed 119 college students. They asked them to rate spam and junk mail on a scale of 1 to 7, with 1 being "most intrusive" and 7 being least.

The results: Spam got an average score of 1.93; junk mail, 4.24.

When the question was rephrased to ask how "irritating" each was, spam got 2.46, and junk mail got 3.87.

The Bother of Using the Trash Can

That may seem like a no-brainer to most of us ... but just why do we think that way? Morimoto and Chang did a focus-group study to get more answers from people.

"They think postal direct mail is less intrusive than spam, as it's easy to toss away and sort out," wrote Morimoto in an e-mail (which did not get eaten by the spam filter in my computer).

"On the other hand," she wrote, "it takes more to delete spam from one's account."

What's more, she said, "people are more task oriented online, and use e-mail not only for personal correspondence but also for work. Spam tends to get in their way to proceed with their tasks."

Direct mail does not have nearly the same effect. It tends to be more obviously different from the other stuff you get each day. (What was the last time your aunt splashed "Free Offer Inside!!!" on an envelope?)

Clipping Coupons

And occasionally, people find a piece of junk mail useful. They do clip coupons from fliers and bring them to the store.

In comparison, perhaps out of fear of computer viruses, they are far less likely to open a spam attachment and print out some 50-cent-off offer.

If you're in the direct-mail business, you're probably not delighted with these findings -- but you'll probably keep sending out fliers. Morimoto and Chang cite numbers from Advertising Age, which said companies spent $52.2 million on direct marketing in 2005.

Morimoto and Chang published their results in the Journal of Interactive Advertising.

And in the time it took me to write this piece, I got pieces of spam with such subject lines as "info string," "waterfall slat," and "top ranking on Google with www.abcnews.com!"