Thinking big about "small pieces"

I am sitting in here in the madness of Vegas and pondering that it wouldn't be here in no one had imagined it. Nothing happens if no one imagines it. The business and financial world we have now, and which to many of seems so broken, is only the way it is because someone imagined it. Imagining things as big and outrageous as Vegas seems like borderline insanity.

One of the challenges for those of us who believe that we are at the beginning of a very significant period of change in how we see ourselves, our societies and our businesses is how to imagine what the future will be like. Having grand schemes and megalomaniac designs seems out of place with something that is in essence personal and intimate.

Part of me believes that we will get somewhere worthwhile if each of us takes the small steps that seem to make sense to us and that in aggregate these small steps will achieve something significant. The other part of me believes that this will confine us to thinking small and achieving less than we could and that without some inspiring, grander and more comprehensive vision we won't make much difference at all.

This ties in with concerns I have about making things happen in a world where making things happen is associated with old values and ways of thinking. How do you bring about significant change using conversations, influence and sticky ideas rather than command and control and grand plans?