Well, not too many car companies are using aluminum, and not too many racing cats are building hulls with it either, but it is very common on Pontoon boats over here.
In respect to cars, sure it is. Land Rovers have aluminum bodies. Mitsubishi Lancer EVO's have an aluminum hood, and front fenders, Nissan 350Z aluminum hood. I'm sure there's tons more too. Theres a company in Ogden Utah that building AC Cobra copies with aluminum bodies as well. They're bodywork is so good they can send em' out polished. They also did a Cobra with a billet aluminum frame, no welds. Really cool stuff there.
