"Flowers"
A forgetful husband thought he had conquered his problem of trying to remember his wife's birthday and their wedding anniversary. He opened an account with a florist, and provided that florist with the dates and instructions to send flowers to his wife on these dates, along with an appropriate note signed, "Your loving husband."
His wife was thrilled by this new display of attention and all went well until one day when he came home he saw a bouquet, kissed his wife and said offhandedly, "Nice flowers, honey. Where'd you get them?"