I am a huge a fan of digg.com -- the community-based website that promotes news articles through a user-based ranking system -- because it brings to my attention news stories I otherwise would not see. A case in point is this 38-year-old article from Time magazine that was published on July 25, 1969 -- just days after man landed on the moon.

In the wake of Neil Armstrong's historic first step, it is eminently forgivable that Time's writers would wax optimistic about the future of spaceflight. In the opening paragraph, the writer predicted that "Americans could land on Mars as early as 1982."

If you were then a teenager as I was, you'll remember that all we had in 1982 was MTV engaging in a bit of shameless self-promotion by replacing the American flag with the MTV logo on the now famous moon-landing video clip.

I begin this week's edition of "All in a Week's Work" with this story because predicting the future course of technology is fraught with danger.

Look closer to home
Nevertheless, while society has yet to put a human on the Mars, most people would agree that technology has revolutionized the world. For example, MTV is a far cry from space travel, but the cable channel was still a pretty cool concept to millions of teenagers, and it's transformed both the recording industry and the world of television.

Similarly, today's YouTube and digg.com are no less revolutionary, and they are forcing traditional media companies such as News Corp. (NYSR: NWS), Viacom (NYSE:VIA), Yahoo.com (NASDAQ:YHOO), Washington Post (NYSE:WPO), and New York Times (NYSE:NYT) to radically adjust their business models to deal with consumers' ever-changing tastes and preferences.

The first lesson of trying to predict the future of technology, therefore, is to stay focused on how technology might actually be used in the home. More succinctly, going to Mars is cool, but most people just want their MTV.

To that end, this week began with the European Space Agency announcing that its Sky-Sailor -- a solar-powered, autonomously controlled micro-airplane -- would be conducting a 24-hour test flight this summer. The agency's goal is to have the Sky-Sailor reach Mars with a decade or two.

I wish the agency all the best, but it is important to understand that AeroVironment (NASDAQ:AVAV) -- the make of unmanned aerial vehicles (UAV) that went public earlier this year -- has already constructed a solar-powered UAV. More significantly for investors, the near-time opportunities for solar-powered UAVs do not lay in space; instead, they will be used for border surveillance, weather research, telecommunications applications, media imaging, and even forest-fire prevention.

Among the more interesting applications to watch for is how companies such as Google (NASDAQ:GOOG) and Microsoft (NASDAQ:MSFT) might make uses of such solar-powered UAVs. Google is already using satellite images, and Microsoft is moving full-speed ahead into incorporating 3-D imaging for user content. Staying on those courses, the companies seem to be on track to give people live coverage of things that really matter to them, such as real-time traffic conditions or, in the slightly longer term, aerial coverage (via the Internet) of your daughter's soccer match at the local park.

It all about you
On another front, this past week saw researchers at Los Alamos National Lab announce they had created a new device for manipulating terahertz radiation. It is the type of development that could lead to a host of advanced communications technologies and might even help manufacturers "see" through plastics and cardboard and inspect packaged objects.

As impressive as that is, though, I would encourage investors to pay more attention to Slacker's announcement this past week that it will be using advanced communication technology to offer "personal radio." What's interesting about this platform is that users can create their own radio stations by selecting the types of songs they like, but then Slacker's "DJ" -- a software program that uses complex algorithms -- picks the content.

This is the type of technology that might find a receptive market and could quickly change the competitive landscape for companies such as XM Satellite Radio and Sirius Satellite Radio.

A final warning
One of the reasons that it's difficult to make predictions is that investors can never be entirely sure how government regulators will respond to new technologies and new opportunities. For instance, officials might very well restrict the airspace that solar-powered UAVs can fly in, and FCC officials might find something troublesome about Slacker's business model.

Such issues, I am afraid, are just the cost of doing business, and while due diligence can minimize surprises, it can't do away with all risk. The one thing investors should not count on the government doing is save them from themselves, as Chinese officials did last week when they banned a company from selling plots of land on the moon.

Thinking about the future is one thing. Speculating on that future is something altogether different. My advice: If a deal sounds like it is out of this world, it probably is. When dealing with new technologies, stick with applications that are a little closer to home.

Interested in a look back at past weeks' progress? Check out "All in a Week's Work" for the weeks of:

Yahoo! is a Motley Fool Stock Advisor recommendation. Microsoft is a Motley Fool Inside Value pick. New York Times is a Motley Fool Income Investor choice. XM is a former Rule Breakers pick.

Interested in staying abreast of the latest advances in biotech, nanotech, information technology, or the cognitive sciences? You can't download the Fool's Rule Breakers service to your brain yet, but you can sign up for a free 30-day trial.

Fool contributor Jack Uldrich is the author of two books on nanotechnology. His latest book, which deals with the exponential growth of a number of emerging technologies, will be published this fall. He does not own stock in any of the companies mentioned in this article. The Fool has a strict disclosure policy.