When you look at a Holden Commodore, you're not likely to see a "green" car staring back at you. (That is, assuming you're in Australia where the Commodore is sold. Or in the UK where you can get a Vauxhall VXR8. Or here in the US where it's rebadged as a Chevy SS or before that as a Pontiac G8 or GTO.) It is, in many cases after all, a big, rear-drive V8 muscle sedan. Not, in other words, known for its frugal sipping of fuel. But that didn't have to be the case.