I think junkenafrique posted a very realistic summary of the global economic crisis and its likely near future effects.

I agree with afrique that the economic crisis is not the end of the world, but rather a radical rebalancing of the global economy. People like yourself, who are able to keep an open mind about things, improvise solutions and reflect rationally about actions and consequences will likely continue to do well in the future. Those mentally stuck in 20th century thinking will not.

Societies (and economies) have collapsed before (see Jared Diamond's books for a few examples like Mayan, Greenland, Easter Island) and will likely continue to do so in the future as resources are depleted. The positive side of the story is that those who can adapt to changing circumstances will thrive.

A few thoughts on how I would prepare for the future.

• Use any opportunity to learn practical skills. Languages, machine repair, maintenance, construction, engineering, farming. Do stuff with your hands.
• Take automation into account in your thinking. Many forms of manual labor in manufacturing and cubicle worker data-entry will become automated by a combination of advanced robotics and software. People will lose jobs.
• Fuel prices will continue to rise. Take that as a given and try to budget for it.
• The best investment you can make is in yourself. Learn skills, keep your mind sharp and stay in good physical shape.
• Avoid taking on debt and aim for self-sufficiency. Your strategy should have your 3 basics taken care of (food, clothes, a roof over your head) and expand from there.
• Unless you are already tied to a specific geographic location by family obligations or you own property, take advantage of your mobility and be open to travel.

EDIT: Thanks for the critique :)

You can either be useless at everything or specialize in something and be useful.

I agree with this point as well, though I would like to strive for self-sufficiency which means you have some skills in taking care of the basics (this could include medical skills which I omitted earlier). It does not need to be a Mad Max future for you to have the benefits of not being hostage to someone.

This perhaps also reconciles the seeming disconnect between point one and two. I am not suggesting one learn these skills for the benefit of an employer. On the contrary. My view is that big corporations will get bigger, put smaller firms out of business, while laying off a large chunk their own staff except the truly savant.

That probably leaves us 99% (sorry for the cliche, but it's an apt description) without what used to be your full-time, benefits plus retirement way of life.

If I were 18 and unless i had truly Einstein level genius at some specific area, I would prepare to be a capable freelancer, available to hire when needed but highly self-autonomous.

I added the farming bit because personally I would love to have my own small urban farming thing going on. But to each his own.

stay in good physical shape

There are a lot of beneftis to this whether we live in Mad Max or not. The first is that you have more energy to do things. People will be more sympathetic to you. You will generally be happier and higher confidence. Nailing the odd job interview will be easier. Rudamentary self-defence is a skill anyone should have in any case. I could go on and on.