The silver lining to the greatest speculative excess in the history of the world (remember how you laughed when I called it that a couple years ago?) is that we've now got a lot of stuff laying around. Not all of it is useful (jet skis, $5,000 purses, etc.), but much of it is. In the Great Depression (hereafter referred to as GD I), there wasn't enough stuff to go around. In GD II, there is plenty of stuff to go around. Homeless? The government can put you up for nominal rent (or free) in one of millions of vacant tract homes it now owns. Need a car? When the government forecloses on GM, it can give the inventory to the needy. You know how Cuba still uses American cars from the 50's? Well, we've got plenty of 2008 Denalis that could last for decades.
Sure, we still need to come up with food, water, and a little energy. But that shouldn't be too big a challenge to come up with enough of them to sustain a minimalist lifestyle. Got beans?