Howard Rheingold wrote a clever piece in the last issue of Strategy Business. It's called Best Business Books of 2005: Seven Ways to See What’s Next (registration required). He presents 7 books he considers as important for future forecast:

These books are at best sketches of what aspects of future life might look like. It’s up to you to weigh the authors’ insights against their biases. But if any of these books seem particularly contrary to your own values, pay closer attention to them: If you want to see clues to what hasn’t happened yet, you need to recognize the meaning of what is right in front of you in new ways. Sometimes, that means looking through the eyes of those with whom you disagree. Precisely because their views conflict with yours, they might be seeing aspects of reality that you fail to see, refuse to see, or don’t want to see.

Everything Bad Is Good for You: How Today’s Popular Culture Is Actually Making Us Smarter by Steven Johnson

In the Bubble: Designing in a Complex World by John Thackara

The Long Emergency: Surviving the Converging Catastrophes of the Twenty-First Century by James Howard Kunstler

Massive Change by Bruce Mau and the Institute Without Boundaries

Radical Evolution: The Promise and Peril of Enhancing Our Minds, Our Bodies — and What It Means To Be Human by Joel Garreau

A Whole New Mind: Moving from the Information Age to the Conceptual Age by Daniel H. Pink

The World Is Flat: A Brief History of the Twenty-First Century by Thomas L. Friedman

Having read some of them, I find interesting the way Rheingold describes what he found which findings are relevant to his concerns.