I'm going to jump in this a little late but I'll have to agree that driving and maintaining an older car is much more environmentally conscious and friendly than buying a new car.

That is taking the raw materials, manufacturing and shipping into consideration.

I can see electric vehicles being the environmentally better alternative in the near future...if our electricity is generated by solar or hydrothermal sources. If not those sources then we're simply shifting our pollution output from our cars to the coal, natural gas or nuclear generation. Heck, there is even an environmental impact form hydro electric sources.

I'll have to disagree with you regarding the big engine required for fun. I'll date myself by saying this but when I was younger the classic Saab 900 Turbo, in my opinion, was what environmentally conscious people drove for fun. It was well built and was fun to drive. It also got decent fuel economy for it's time.

By no means was it an equivalent for our e38 750iL though. I own a 2001 750iL for my daily driver and although it gets worse fuel economy than my 2001 330xi it still is considered a LEV. And burns cleaner than the old Saab 900 Turbos I mentioned.