Years ago, one of my favorite authors, Neal Stephenson, wrote a book called The Diamond Age. Set in the near future, technology had progressed to a point where most homes had a refrigerator size machine that could make virtually any common household item, most often out of diamond. Why diamond? Because the raw material is as cheap as, well, dirt--it's just carbon. Advanced microfabrication at the molecular level enabled the machine to build an item layer by layer at the molecular level. One thing that was handy in the book was diamond knives that never got dull.
Sound far-fetched? It's not. Industrial designers have been using polymer-based rapid prototyping machines for years to create three dimensional objects out of a soup of light-sensitive liquid plastic. A laser, driven by CAD/CAM information, hardens the plastic layer by layer, and the object "grows" right out of a container of goop.
More recently, some scientists have been using modified ink-jet printers to spray bio-compounds onto a sheet of plastic to create things like cartilage-based ear replacements for people that have suffered injuries.
Now we have the Replicating Rapid Prototyping Project, or RepRap. This UK-based university effort intends to build an Open Source system that can build complex objects. We won't have these in our homes any time soon, but our kids may. The Open Source approach--making it available for anyone in the world to both use and improve--has the potential to transform the world economy. What are some of the implications? Well, China might not have the economic clout it has now if common household items can be fabricated cheaply near the user of the item. The current "consumption" society would change radically as anyone could acquire almost any common household object for the cost of the raw materials--the cost of shipping, advertising, distributing, warehousing, and retailing would disappear.
What would all those people do? Well, for one, there would be a big market for the one thing the machines can't do--create the designs. I also believe that handmade and handcrafted items of high quality would become very popular.
How about effects on other future weak signals? For one, RepRap machines would make colonization of the moon and Mars much easier. You'd simpy ship a few RepRap machines to the moon, feed in silicon, carbon, aluminum (moon dirt, basically), and nearly everything a growing moon colony would need would come out the other end. Ditto for Mars.
We're just a short ways into the a long cycle of enormous growth and change. Recall that the Industrial Revolution started in the early 1700s but did not really flower until the early 1900s, nearly two hundred years later. If you mark the start of the Digital Age at 1950 when the first commercial computers became available, we're only a quarter of the way into what I think is going to be another two hundred year cycle. If you can't imagine where your community should be in two hundred years, how about fifty? Are the majority of your community leaders still looking to the past for guidance?
Communities that learn to think in a future context, rather than a past history context, will thrive no matter what technology emerges.