The basics: more than 50 percent of all e-mail is spam and it costs U.S. companies at least $1 billion per year in security and human resources expenditures, as well as lost productivity. Increasingly, virus-infected machines are used to distribute spam and perpetuate additional fraud, such as phishing. Several antispam technology approaches have been proposed in recent months. I talk with Peter Christy of NetsEdge Research about various approachs from Yahoo, Microsoft and others for fighting the plague. Video