Nokia is making a mobile cell phone that lets you write short text messages in mid-air.

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.

More here.