If you have not read George Monibot's "Feral" yet. This BBC feature is a great (and very eye-pleasing) summary of his thesis:
BACK TO NATURE
"Civilization is boring. It has many virtues, but it leaves large parts of our minds unstimulated. It uses just a fraction of our mental and physical capacities. To know what comes next has been perhaps the dominant aim of materially-complex societies. Yet, having achieved it, or almost achieved it, we have been rewarded with a new collection of unmet needs. Many of us, I believe, need something that our planned and ordered lives don’t offer."