Is it a green product or a waste of money?

Sometimes we have a choice between a standard wasteful product and a greener one - it's a clear choice. And other times, well, it's harder to tell the difference.

Take this device. It cools your car for you on hot summer days! What a nice idea - it makes coming back to your car after its been sitting in the sun a pleasure.

But really, do we need such a device? Wouldn't it be better if we could just park in the shade of a nice, green tree instead of parking in the sun? (or better yet - not drive our cars on hot summer days at all and walk or bike?)

Maybe this is something that we all should have. A little fan to keep the car cool. Or maybe not. Just because it's solar powered doesn't mean it's cool.