I'm impressed - four posts in, an no mention of Dolly Parton yet.
Until I fitted a doorbell about a year ago, we relied on a clapper (don't think it could rightly be called a knocker) thingy attached to the letterbox. But I often missed it, working as I do, at the very back of the house. Since I fitted the doorbell, I never miss a caller. I'm seriously thinking of removing it soon.