I just read Bill Buxton's very interesting Sketching the User Experience, the thesis of which is well-summarized here. (This is no substitute for reading the book!)
The last two pages of the book are hugely relevant and they really resonate with me.
Buxton quotes a Design Exhibition he was involved in:
Its not about the world of design; its about the design of the world.
Now that we can do anything, what will we do.
He quotes Toynbee...
"The 20th century will be chiefly rememered by future generations not as an era of polotical conflicts or technical inventions, but as an age in which huan society dared to think of the welfare of the whole human race as a practical objective."
...and then he comments, "Now, rather than just daring to think about it, in the twenty-first century it is time do do something about it."
He quotes T.E. Lawrence....
"Those who dream by night in the dusty recesses of their minds wike in the day to find that it was vanity: but the dreamers fo the day are dangerous men, for they may act their dreams with open eyes, to make it possible."
And concludes the book with...
"May you dream in the the day."