The botnets are coming to a Windows PC near you
The November 20, 2006 article "Spam surge linked to hackers" from eWeeks is a must read. Unfortunately, I can't find the actual online version of the article in print.
The article discusses the increasing complexity hackers are using botnets running on tens of thousands of hijacked Windows computers to spread spam. The article focuses on the research by SecureWorks regarding the malware trojan called Troj/SpamThru. Some scary unique features have been identified with this trojan including: