I did know about the dots. I’ve been receiving emails addressed to someone with the same name, but people using gmail instead of hotmail or some other provider. And they also don’t know about the fact that putting any number of dots in doesn’t change a thing.

But I only recently learned about the + sign, when my wife found that out by accident, using +1 after the first part of her email address. So I tried that with my own email and used +2, +A and a few more options. When all that worked, I wanted to find out if this was a general feature, which was how I arrived at this site.
Thanks, Dan, for sharing!