A BICYCLE.

To ride on a bicycle is one of the best exercises for health, as you work less.
A bicycle occupies less space than a car.You can forget petrol, the ITV, the taxes and saves money in insurances and in repairs.The bicycle reduces the number of cars and reduces the pollution.It makes you feel free, and independent. You can also forget traffic jams and problems of parking.The bicycle is faster than the car in short urban distances.It is more efficientb that the car in energy terms, consumes 12times less than a full car to carry a person.
This would help to be more ecological.