If you can’t hear it when people knock on your door then a solution is at hand (literally) via the Knock-Knock Door Chime.

Unlike regular doorbells this one doesn’t have a button for your visitor to press, they simply knock on the door and this gadget will sense it and set off the chime, so no more ugly doorbells. What next a doorbell that makes a knock knock sound. Actually I’m surprised you can’t get an MP3 playing doorbell that you can download tunes too maybe it could be yet another iPod add-on, the iChime.

Anyway the Knock-Knock Door Chime is a real product and available for $49.95.