Mail Box Buzzer
Like most people we still get a large amount of important snail mail through our postal services, but we never know when the mail gets to the mail box since our windows and doors are too far away or we had no outgoing mail for the flag to be put up to tell us the mail has finally arrived.
If we had a caller I.D. type log or a buzzer the mail man could push then we wouldn't have to guess or run out to check the mail every half hour or more for the many differing hours the mail might arrive. The Buzzer/Bell/I.D. would be remote from the mail box to the inside of your home for ultimate ease.
Reward: A free instalation and free life time use if a fee would apply (very doubtful).