An anonymous reader writes "A recent study on spam has revealed that spammers see a return between 4.9% and 6% when selling stocks they have bought low and spammed the world with." From the article: "The researchers say that approximately 730 million spam e-mails are sent every week, 15% of which tout stocks. Other estimates of spam volumes are far higher. The study, by Professor Laura Frieder of Purdue University in the US and Professor Jonathan Zittrain from Oxford University's Internet Institute in the UK, analysed more than 75,000 unsolicited e-mails. All of the messages touting stocks and shares were sent between January 2004 and July 2005."