I've been trying to research claims by this Hill's group about thermodynamic collapse of oil:  http://thehillsgroup.org

It's something that will obviously happen eventually since we take all the low hanging fruit first, but they're claiming that within only 10 years 75% of gas stations in the US will be gone, which is a pretty big shocker for ending of fossil fuels in modern civilization.  I know that peak oil seems to have occurred in 2004 (peak of conventional, high return on investment crude production and not low return shale/fracking/etc), so it looks like there's going to be some mega paradigm shift somewhere along the lines here.  The only question is when it occurs.

The part that makes this a more immediate event is that other sources claim you need $120 a barrel oil to bring new and not existing sources online right now (and oil is currently $50ish).  Some people say, well, the free market will just jack up the price to fix it, but that's not really possible in the following scenario.  Let's make two assumptions, that you have a drive to Walmart economy where people are blowing lots of energy to travel long distances to buy things, and that cars (specifically delivery vehicles) will not get significantly better MPG.  If the market cannot bear $120+ a barrel oil, the price doesn't go up with supply continuing to flow, the drive to Walmart economy simply ceases to exist, demand collapses, and nobody drills the oil.  

The oil has been constrained from being delivered to market both due to production costs that the average human can't afford, and the fact you eventually reach a point where it requires more energy to extract than it gives you.