You are driving down a dual carriageway... traffic lights some 300 metres ahead have just turned red.....
Just take your foot off the accelerator pedal and cruise to a stop... even better if you can time it so that you simply have to change down a gear or two (assuming manual gear box) and carry on through as the lights change back to green.
As oldhamfan says, non aggressive acceleration and braking will save you loads of dosh !