You could win a new Opel by driving with the least fuel over a 20km stretch in an Opel Corsa 1.3 CDTI, Astra 1.3 CDTI or a Vectra 1.9 CDTI. The contest is going on through 25 August at Opel dealers throughout Germany. The most fuel-efficient driver in each of the three models from each dealer will qualify for to win one of 50 eco-efficient Opel automobiles. Presumably Opel will have the cars set up with optimal tire pressure, topped up with light oil and carrying a tire repair kit rather than a spare, following their own fuel-saving tips (German). Drivers are advised to plan your trip to avoid stop-and-go or jammed traffic, look ahead to minimize braking, shift early to keep rpms low, and stay in gear rather than roll towards stoplights. Don't be afraid to turn the engine entirely off even for standing times as little as 3 mintues. And, of course, don't even think about switching the air conditioning on. With this action, Opel wants to highlight how much driver behavior can influence the CO2 output and money-burning performance while driving. To improve your chances to win, check out tips on fuel efficient driving: Light on the pedal, light on the planet video, TreeHugger Homework or eco-driving.