Yesterday, my co-worker Matt told me about some Gmail tricks.
With a Gmail email address, the characters after a plus sign are ignored. You can use this to generate a new email address for yourself any time you need one.
For example, (assuming your email is email@example.com) you could sign up for amazon.com using firstname.lastname@example.org. All your email will be routed to the same place, but in the future you can filter or block based on the unique email if you need to.
This means you can track who gives your email to spammers. So, if you start getting email from Joe’s Used Cars addressed to email@example.com, you know Joe stole (or purchased) your email from Amazon!
The other trick is just “nice to know.” Gmail will ignore (some, all?) punctuation in email addresses. So firstname.lastname@example.org is the same as email@example.com. If you want to make your email look more formal, you can add a period between first name and last name. If you’re trying to guess someone’s email address, know that that the periods don’t matter.
“you can block certain services and track who gives your email to spammers”
well, as long as they don’t just filter out the +part