Nokia is making a mobile that lets you write short text messages in mid-air.
Wave and talk with the 3220
The messages are written using a row of LEDs fitted on the rear cover of Nokia's forthcoming 3220 phone.
A motion sensor in the phone makes the lights blink in a sequence that spells out letters when the handset is waved in the air.
A trick of human vision turns the sequence of letters into a message that hangs in the air. The phone is due to go on sale in the summer of this year.
The 12 lights on the rear of the clip-on cover for the 3220 can be used to spell out words or display symbols.
Messages will have to be even more terse than the hugely popular text messages because the air texting system can only handle a maximum of 15 characters.
Messages are formed with a row of LEDs
Nokia said the message can be seen from about six metres away in daylight but much further when light levels are low.
The messages appear to float in mid-air thanks to a quirk of human vision which means we see the image as a whole rather than in pieces. In the same way we see the action in films as continuous movement rather than as a series of stills.
Key to the air texting system is the motion sensor which works out when the phone is being shaken and illuminates the LEDs in the correct sequence.
This sensor is also used to play some games supplied with the phone. A player navigates them, an airboat race and a flying game, by tilting the phone to make on-screen vehicles steer around obstacles.
Nokia said the 3220's air messaging system could be used by friends to talk to each other across crowded rooms or open-air concerts.
But the unveiling of the phone proved popular on weblogs with commentators who speculated that it could be used to play games overlaid on city streets, as a heckling device or a novel way to interact with other devices.
The clip-on cover is sold separately to the 3220 phone.