The TechZone shows you how spammers operate and how to flight them.

Spammers trade email addresses for money. This is why the system is out of hand - it is an income producing activity. Every email address has a value to it and no matter how little the value, putting together a list of 100,000 can provide a neat income for a spammer. Most spammers have spam lists many times larger than this.

Understanding How Spammers Work