Found something interesting from tech insider a couple a days ago..

http://www.techinsider.io/do-you-nee...-winter-2015-2

Its actually a sticker fore the car, and i bought it.. So today it arrived after some days traveling from US to Europe.
I will properbly put it inside the cars back window as i dont want stickers on the car, but the idea is good to tell others that i drive GREEN