Your Gmail address can look like this: a.ddress@gmail.com, ad.dress@gmail.com, a.ddre.ss@gmail.com etc. Gmail ignores all dots in the
username. But if you registered Gmail account with dots in the username you have to log in to Gmail this way. Also there is another trick with addressing. Your
username can look like this:
username+newsletter@gmail.com. It is good way of sorting your mails. Just create label Newsletter, then create a filter which will recognize
username+newsletter and automatically label and archive it. It is very
helpful. Unfortunately you can't sign up with "+" everywhere...