Extreme Survival Skills of the Poor

When most people think of extreme survival skills, they often think of Bear Grylls or one of these top survival experts level of skillfulness.  While there is the (slightest, most minute) possibility that you will find yourself in a situation where you would have to drink your own urine, make a fire with a couple of sticks, or shoot your way out of an ambush, it's much more likely that you will have to survive a situation that has to do with weather (of the really bad kind), money (or the definite lack thereof), or some sort of societal collapse (always a bad thing).  Do you have the skills to survive these sorts of extremes?  Learn from the poor and homeless how to make do with very little:

• The homeless, while often the most vulnerable in our society, have generally developed some pretty good survival skills when it comes to shelter and keeping themselves safe in difficult environments.  Some skills here, here, and here.
• Poor people do things such as dumpster diving, trash picking, and otherwise living off the excess of others in order to stretch their limited cash.  Even more extreme is using animal medications which are cheaper than going to a doctor to treat their ills.  
• And there are several lists of really-poor-people skills that can be rather eye-opening--and useful.  Like this, this, this, and this.