It's hard to go into a bar and explain your job to a woman by saying "I advertise penis enlargement pills online," Ed said. "It doesn't go down very well."

He rationalized his actions by saying spamming is not like robbing someone, although the lurid impact of spam was clear. Some 9 million Americans have some dependence on prescription drugs, Ed said, and he noticed that the same people were buying different drugs each month. "These were addicts," he said.

Additionally, "the product is always counterfeit to some degree. If you're lucky, sometimes it's a diluted version of the real thing," he said. Viagra is cut with amphetamines, and homemade pills are common from sketchy labs in countries such as China, India, and Fiji, Ed said.

So Ed got out of the business. He's written a book, "Inside the Spam Cartel: Trade Secrets from the Dark Side," which he said has had some take-up in law enforcement circles eager to learn more about the spam business, which he projects will only get worse.

As broadband speeds increase, spammers will increasingly look to market goods by making VoIP calls or sending out videos, Ed said. The ultimate unsolvable problem is users, who continue to buy products marketed by spam, making the industry possible.

"I think in 10 years we'll still get spam," Ed said. "Be prepared to be bombarded."