Over the past 5 years, spam sending technology has improved dramatically. Static messages sent opportunistically through misconfigured hosts have evolved into dynamically generated, subtly obfuscated messages sent on a massive scale by special purpose malware. We present a survey of three generations of the most popular spam sending tools, focusing on how they have improved over time. The paper conclude with a case study of a modern spam campaign, showing how the spammer has used randomization to make their messages more difficult to detect by content filters.