Get spammers back, and send your own message telling them to stop spamming once, a thousand times, or as many times as you want back to them. And get a hi-score at the same time.

• Bounce Bully 1.0
  Bounce spam messages back to the spammers who sent them, making them think your email address is invalid. This may encourage some spammers to remove you from their spam lists....

• Spam Bully 2.0 for Outlook 2000/2002/2003 2.0.0.80
  Spam Bully 2

• Spam Bully 2.0 for Outlook Express 5/5.5/6 2.0.0.79
  Spam Bully 2.0 is an easy to use self learning spam filter that integrates into Outlook Express. Uses Bayesian artificial intelligence to learn from your personal email habits. Quickly learns what you consider spam and not spam. The more you use...

• Get Rid of Spam Email Forever With This Fantastic Software From SpamItBack 9.0
  Most people would agree that spam emails are a big hassle when it comes to organising your electronic correspondence