A year ago, Lexus were censured by the UK Advertising Standards Agency for running ads for their hybrid SUV, claiming it was a planet saving breakthrough. The ASA ruled that as the car emitted 192 g/km CO2 compared to 158 g/km CO2 for an average European car (of all classes), it could not be portrayed as green and banned the ad.

Lexus have now bounced back with the 2010 model which emits 148 g/km CO2 - a big luxury car which emits less than the average vehicle. It's amazing how a little public humiliation can drive a technological breakthrough.