You’ve got mail

Today I was thinking of a small device that connects to the internet.  the sensor on it will note when you get mail in your physical mailbox.  It will send you an email.  this sounds lazy but would be useful for some people.  if your mail box is hard to get to because of a disability or its a PO box miles from your house,  so you do not have to waste gas on a no mail day.  The post office at least has the capacity to tell the website when a package was delivered so adding this feature should integrate some what easily and cheaply for PO Boxes.