Thoughts from a reflective educator.
We all know the end of oil is coming, and with it, the end of cheap energy. Biofuels, alternative energies, all of these are only going to get us so far. One of the major consumers of energy on this planet is the shipping of goods across the globe. We ship supplies to one part of the globe, and then ship manufactured products back again.
Imagine if instead of having to ship goods, we could ship 3d digital models over the Internet instead, and then print these on demand. At first, products could be printed in local manufacturing plants (perhaps even on the same grounds where customers would go to pick up their orders, which would also significantly reduce warehousing needs) and supplied to local consumers, and eventually, consumers could print their own models directly, perhaps paying for licenses to create these products, or for the equipment necessary to do the production themselves (and have some licensing costs built into the cost of the equipment). Imagine an ecosystem where the consumer is the designer and manufacturer of their own products and that those products weren't limited to what capability the consumer has with typical DIY tools.
As production rose, so would production quality, and ever more intricate devices could be constructed with these machines. With the inclusion of the open source model, much of what we pay for today could be nearly free as we would just have to pay for the machines (and the energy to run them) and the supplies necessary to construct the models.