Catching Email Resellers with the + Sign 
Published on Oct 10, 2012 by Jamie Munro
I'm sure you're like me and register to new websites almost daily giving them the same old email address each time or if you are even really anal about it, creating a new email account for each site. Then all of a sudden our email box starts getting more and more filled with spam, what's the big idea?This is a neat one that I feel a little late to the game with, but hey why not, it might help someone out there!
I'm not 100% sure how many mail providers allow for this, but GMAIL is definitely one of them that does. If you want to easily track down how spammers are getting your email, each time you register for a site, don't create a new email account, and instead make a slight – legitimate – alteration to it!
Say your email is test@gmail.com. When you go and register at Facebook, instead of using this email address, change it to the following: test+facebook@gmail.com. Google ignores anything after the "+" sign, BUT it will show up in your inbox exactly as typed.
Now when you start getting spam email, check what the TO email address is, if there is a "+" sign and the name of a website you registered at – bam – you know who just sold your email address!