Kevin Kelly is a provocative thinker on this stuff. (He created the original vision that became Wired magazine, though he never gets credit for this... credit went to the folks who kicked in the money.)
http://www.ted.com/talks/kevin_kelly_tells_technology_s_epic...
Kurzweil also talks about history of technology when he talks about accelerating returns.
It's useful to think way back imho... for example, language is a very early example of a technology.