Sometimes, as they say, a picture is worth a thousand words.
I was recently at a scientific conference on the development of sustainable biofuels, this being my lab's research focus. Much data was presented and much was said of substance. But the one slide I made sure to get a copy of was this one from Steve Mayfield at UCSD, conveying the history and availability of petroleum at current usage rates (more information here):
Have we really even begun to take this in yet?