Kathleen Higgins has had the same e-mail address since 1994. She has used it to subscribe to e-mail newsletters pertaining to cooking, investment, health and fitness, real estate, home renovation and other topics of interest. She has posted it on several Web sites and used it on her own Web site. Little did she know that spammers were harvesting it.

Ms Higgins, who works in Calgary, Alberta as a personal assistant and shopper, now receives in excess of 200 spam messages per day. She has tried a variety of filtering techniques to combat the onslaught but none worked "particularly well," she said. Currently, her email reader is set up to check incoming e-mail against contacts in her address book. Only e-mail messages from "recognized addresses" make it into her in-box. The rest are diverted to another folder. She then separates legitimate e-mail from spam. "It's all very labour intensive and frankly not at all foolproof," she said.

Spam is out of control. According to various research firms, spam accounts for about 40% of the billions of e-mails sent each day and the plague costs companies nearly $20 billion (all figures US) worldwide in lost productivity and expenses.

While spam about Viagra is irritating, and spam with links to porn sites is offensive, spam can also contain viruses or be used to gather information related to identity theft and fraud. The FBI estimates that cyber-crime, much of it originating with spam, cost consumers and businesses about $400 billion in 2004.

America On-line, Inc.'s 28 million members receive about three billion e-mail messages a day. Over 80% of the messages are rejected as spam before they get to the user, said Alex Leslie, vice president, technology, for AOL Canada Inc. A team of 100 AOL staff members combat spam daily, and still AOL members receive junk e-mail.

E-mail that is not rejected outright as spam is run through additional filters. Suspect messages land in spam folders that subscribers can view to ensure there are no false-positives, legitimate e-mail tagged as spam. They can report spam with the click of a button. Reported spam dropped by 75% in 2004 as AOL improved filtering, said Mr. Leslie.

Not all Internet Service Providers (ISPs) filter spam as effectively as AOL. Many small and medium enterprises, receive e-mail through Web hosting companies using no filters or less sophisticated filters. And users spend hours each week cleaning up the mess.

"It doesn't have to be this way," said Tristan Goguen, president of Internet Light and Power (ILAP), an Internet company based in Toronto. Last year ILAP combined its iPermitMail spam filtering service with an anti-spam technology, Sender ID, that verifies the source of e-mail. If a message purports to be from the Royal Bank, for instance, Sender ID verifies that it is or blocks the message.

This ends phishing attacks, said Mr. Goguen. In a phishing attack, e-mail disguised as coming from a reputable financial institution urges the recipient to click on a link to update personal or credit card information. The link takes the victim to a fake Web site designed to look legitimate. Any information entered is routed to the scammer and used for fraudulent purposes or identity theft.

iPermitMail users pay a few dollars per month and "train" the system over a couple of weeks to recognize the difference between legitimate e-mail and spam which, Mr. Goguen claims, eliminates 99% of all spam without incurring false-positives.

Some companies are so fed up with spam and e-mail administrative chores, such as updating anti-virus software, that they outsourced e-mail to companies like Ceryx Inc., a Canadian e-mail management company with operations in Toronto and New York. For about $20 per user per month, Ceryx filters spam, keeps anti-virus and security patches up to date and maintains redundant servers to keep e-mail moving even if one server crashes.

Spam messages for some Ceryx clients have dropped from hundreds or thousands per day to one or two, said Gus Harsfai, Ceryx president. Companies that outsource e-mail to Ceryx keep their existing e-mail addresses and e-mail still arrives, via the Ceryx servers, on their computers.

Business owners who want fight spam on their own can use programs such as SpamBayes, SpamAssassin, MailWasher and others. Some anti-spam programs separating the chaff from the wheat by filtering suspected spam messages into a separate e-mail folder. Other programs, such as MailWasher, let users see what is on their ISP's server so they can delete suspected spam before downloading e-mail. MailWasher can also be programmed to automatically identify and delete spam.

All spam-blocking systems take time to set up, learn and manage. And they are not perfect, as Ms Higgins knows first hand. While it is her job to help "busy people do things they don't have time for," she needs someone to help her combat her horrendous spam problem, because combating it on her own is eating into the time she has to help her busy clients.