Slashdot pointed the way to an interesting article at eWeekM on the recent surge in e-mail spam hawking penny stocks and penis enlargement pills. I've seen a huge spike on LISHost recently, and they says it's due is the handiwork of Russian hackers running a botnet powered by tens of thousands of hijacked computers.
Internet security researchers and law enforcement authorities have traced the operation to a well-organized hacking gang controlling a 70,000+-strong peer-to-peer botnet seeded with the SpamThru Trojan. Think about that number for a second, 73,000.... In all, computers in 166 countries are part of the botnet, with the United States accounting for more than half of the infections.
They say With a botnet of this size, the group is theoretically capable of sending a billion spam e-mails in a single day.