Fairfax (Map, News) - Tom Caldwell is hoping that what is an annoyance for most — namely, spam e-mails — will become a profitable business for him.

The chief executive officer is the founder of Idalis Software Inc., a Fairfax-based startup company formed last year devoted to anti-spam software and services. The company was among five promising new firms chosen to present to potential investors at George Washington University’s Grubstake Breakfast Tuesday.

Idalis’ product is a Windows-based Anti-Spammer system. It differs from traditional anti-spam software because it tracks down the source of the spam before it is sent to an individual’s mailbox, Caldwell said. In its beta version now, the system has been able to block 96 percent of spam E-mails before they arrive, Caldwell said. Idalis is also able to track what are known as “spam zombies”, as when a virus is able to take control of a computer and send out spam disguised as legitimate mail from known users.

The software will be on the market in the next two to three months, Caldwell said. Idalis also will target large companies that do not use Windows-based systems by selling them its list of blacklisted Internet Protocol addresses sending spam, Caldwell said.

Caldwell, a former spammer himself before the practice was outlawed, was drawn to the anti-spam market, which is valued at around $2.8 billion this year, and expected to jump to $5 billion by 2010, he said. Spam e-mails are increasing at a rate of about 20 percent a year, he said.

“Right now, there’s no clear market leader,” Caldwell said.

Dan Burrus, CEO of Burrus Research, a Milwaukee-based technology research and consulting firm, said Idalis should be successful if it is able to adapt to spammers’ changing methods, and if it takes a proactive rather than a reactive approach to finding spam.

“There’s always room for another entrant in the market because the nature of spam keeps changing,” Burrus said. “The spammers, they don’t sit still.”

melissa.frederick@dcexaminer.com