Cool Gmail Feature -- Periods do not Matter

It's true: john.doe@gmail.com is the same email address as johndoe@gmail.com as far as Gmail is concerned. And to think that everyone makes such a big fuss about making sure you have that period in the right place when they give out their emails...

This feature is documented in Gmail help here. Gmail even idiot-proofs this feature by having a link to the docs when you receive an email at a different address from the one you registered (see photo).

Some have used this feature to their advantage to reduce spam or create multiple accounts on a web service that all send mail to the same Gmail address.