Invention: “Ever been plagued by wrong numbers or midnight calls from far-flung time zones? No problem, says SK Telecom of Seoul.

Instead of the caller getting a standard brrrp-brrrp tone after dialling a number, their system allows subscribers to play a personalised message back to the dialler.

The approach works for fixed or cellphone lines, and the message heard by the dialler can be the subscriber’s number, name or nickname, interspersed with normal ring-tone and the time of day at the subscriber’s end. So anyone who has mis-dialled, or called from across the world and forgotten the time difference, immediately knows to hang up.” (New Scientist)