Over the years I have become a fan of what is called the Singularity. It is a time in the not so distant future when technological progress goes faster than the ability to predict it. Essentially, progress in medical science, computer hardware, artificial intelligence, and nano-technology is exponential in nature and some 30 – 50 years from now, progress accelerates to the point where the curve points straight up. http://www.singularity.com/