Where does Spam come from?

I made a simple study on the last months to see where spam might come from (I'm talking here about real Spam like pills and fake software).

I created 4 email addresses:
1 - An address only subscribed to CNN daily news
2 - An address only subscribed to CNN daily news & a couple of adult websites
3 - An address only subscribed to CNN daily news & posted on this website
4 - An address subscribed to CNN daily news & the same adult websites and posted at the same time on this website.

What turned out was that only addresses 3 and 4 got spammed and they received exactly the same Spam messages - this clearly indicates the reason for being spammed is the same.

One thing that I know but failed to demonstrate on this test is that a lot of spam also comes from your contacts that have their email address hijacked.

The great surprise came from the fact that no Spam was ever sent on the emails used to register on adult websites.

The email addresses posted on this blog received spams in the days following the post and now have a ratio of 28% (38 out of 98) of spam.

Conclusion is :
You probably can have a Spam free email if you never post it anywhere and don't give it to anyone.

Maybe that could be a good resolution for 2009 ;-)