Until we learn to live more sustainable lifestyles, we’re going to be faced with more ‘peak stuff’, where demand for a particular resource exceeds supply. Fast Company has a nice article on this subject if you want to read more. One example is clean water. More people equals greater demand, but resources are diminishing as glaciers melt and some aquifers are depleted. Food is another one, though the system is so wasteful (in this country at least) that I’m optimistic we can make some big improvements there. Or at the least, stop burning food (turning corn into ethanol to power cars).