When I saw "cash is king" I first thought about the financial context these days. If you can generate or hold onto cash, you are truly "king." Cash equals control and opportunity, and a strong negotiating position. Consumer debt, sadly, represents the opposite. Financial survival is a probably a topic for a different thread.

I agree that legal tender in small bills is a wise hedge against the inevitable failures of our wired world. Systems fail. Cash always works. I always have enough cash for a meal, a tank of gas, etc. -- the stuff that will get me home.