If you want to create a fullsize background image on your website you can simply use the CSS3 property background-size: cover. But not every Browser supports CSS3 so you need a fallback. Check out this tutorial to learn more.
If you want to use an image in your responsive web design you can use fluid images. But there is another way. You can set a maximum height and crop the image. If you want to learn more about it, check out the tutorial that I wrote about the overflow image cropping.
A few weeks ago I showed you some retro ads of the AMC Gremlin. While searching that ads I came across the AMC Pacer, which I think looks even cooler. The retro futurism design with rounded shape and massive glass area is simply amazing. I think it looks a little bit like the vehicle from the Jetsons.