SCIENCE AND TECHNOLOGY SPECIFICS:
The book "Engines of Creation" by K. Eric Drexler saved me from something of an existential angst during the late 1980s. Not that it gave me some great spiritual or philosophical reason to exist, but it painted a picture of the relatively near future--within my lifetime--in which technology can make almost anything using molecular manufacturing (otherwise known as nanotechnology). We may be living in a period of such profound technological change that we'll see far more amazing developments in a few short decades than entire centuries and even millennia have witnessed. Instead of just being born, living a normal life, and dying while experiencing few world-altering technological advancements--like most people throughout history--those of us who live to see the next few decades will likely see changes that completely redirect social paradigms and may even see the definition of what it means to be human change completely. These changes may include home factories capable of creating virtually any technological item in a short time for mere pennies, houses that quickly alter configuration to look like anything from a mansion to a tropical beach to a fantasy world, virtual worlds as "realistic" as the real world, copying human brains to robot forms that appear completely human but with far superior function in all areas.
In short, the vision presented in Engines offered me something to look forward to. There are no guarantees, of course, and there are plenty of scientists and engineers skeptical of this vision...but I've seen the concept of nanotech go from fringe science to mainstream science within a decade. Now it's no longer a question of if, but when and how profoundly will it change the future. I look forward to seeing if such change actually comes about.
Since reading Engines, I have kept a close eye on the development of nanotechnology, noting the mileposts and seeing if it remains on track for arrival (by around 2025). So far, so good. In mid-2008 I started my Advancing Technologies blog to keep track of articles describing recent technological developments leading directly or indirectly to a nanotechnological future (I've lost a few years of articles by just sending out the links as emails instead of blogging them, but better late than never...).
Another visionary who caught my attention is Ray Kurzweil, an inventor and a futurist with a strong track record. He has written extensively about the "Law of Accelerating Returns" (basically an extension of "Moore's Law"), which observes that certain aspects of technological development grow at double exponential rates, and have been doing so for all of computational history, and perhaps all technological history and even biological history. Extrapolating this pace of change on a chart leads to a "technological singularity"--where change occurs so rapidly that in the near future the graphed line goes almost straight up. The implications are profound: machines that so far exceed human capabilities in all areas that we may have to become machines ourselves in order to not be left behind in their technological dust. And nanotechnology is the most likely pathway to that future.
Anyone interested in the topics should read Engines, as well as "Unbounding the Future" by Drexler and Chris Peterson, "The Age of Spiritual Machines" (my favorite) by Ray Kurzweil, and "The Singularity is Near," also by Kurzweil. Kurzweil also has a website filled with articles exploring these concepts and more.
The exponential growth of computing.
An example of a molecular-scale machine.