For example, motorists using a hand-held phone will see the words 'Mobile Phone?' while speeders will be told to 'Slow Down!'. Anyone who's not strapped in and gets seen will be reminded with 'Seat Belt?'.
The sign - which is a first for the UK - has eight pre-programmed messages and is about to be trialled in Oxfordshire. "It will be like a tap on the wrist for drivers, but in a nice way," said Steve Wood, the county's safer roads officer, who came up with the idea.
If it improves road safety significantly,` the system - which has already been dubbed the 'snitch sign' - will be rolled out across the region. It could eventually go nationwide. It was unveiled at the recent Traffex exhibition for the traffic engineering industry at Birmingham NEC, and has been developed by Middlesbrough company Varitext.
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