Instead of making a list of all combinations, why don't you remove the DOT from gmail addresses? Just remove it the moment someone enters it.
There's not really a point of listing them, as they all belong to the same account. The owner can make endless combinations.
wonderful, this is just the same email spelling only difference by punctuation mark, this ought to have been stopped by gmail email services it self.
It's a feature, not a bug! My.Name@gmail is the same as MyName@gmail, you can add as many dots as you want, gmail ignores them.
Just like MyName+thisisanalttoearnextra@gmail goes into the same mailbox. To fight these spam-accounts, ignore the part after the PLUS, and ignore all dots.
I'm not sure what other email services have this functionality too.