Recently I came to know about a Gmail ‘feature’. See here. If u have an email ID as IAmCool@gmail.com then it is same as IAm.Cool@gmail.com or I.A.m.C.o.o.l@gmail.com. Point is that Gmail simply ignores the dots. Hence for all the metioned cases, Gmail sees them as only IAmCool@gmail.com. Now if I create an account IAm.Cool@gmail.com then I can get all the mails IAmCool@gmail.com receives. A big threat to his privacy. But there is catch. While creating Gmail accounts, it ignores the dots then also. Hence I can’t create IAm.Cool@gmail.com when IAmCool@gmail.com already exists, and the threat is taken care of.
But I got a jolt, when I was contacted by a person using Gmail to stop sending mail to him, but he was not in my contact list! Further investigation revealed that his ID is the same as that of my friend’s, but, different only by the lack and presence of a dot in their IDs. This should not have happned. I tried creating such a ‘sibling’ ID of my ID, but I failed. I don’t know what caused this faux pas, but I hope Google fixes this up soon.

If u figure out what caused the creation of such ‘sibling’ IDs then do post a comment here.

Update: Google help desk has assured after investigation that the dotted ID is not my friend’s as I claimed, but it too belongs to the stranger. I have been advised to contact my friend for comfirmation. I will ask him.