play with me by annick collins from uk

This uses the idea of interaction with sound and personal identity to replace the traditional nock on the door.

The interaction is in the form of musical prayer wheels which are laid out like the keypad of a mobile phone, so it is intuitive to use. Instead of ringing or knocking the visitor is enticed to enter their name/ or a message by rolling the wheels until the letters spell out the text. As they roll the wheels, allocated musical sounds are emitted. If the visitor is regular the sound made by their name will become recognisable to the people that live there, as traditionally the individuals nock becomes associated with them. This lets the homeowner know who’s at the door before opening, increasing security.

If no one is at home the visitor has the choice to leave a message on the screen by playing the wheels.