Interesting that the "golden years" of NASA and the rural electrification era have been mentioned - both are on my time-machine "itinerary" as well!
BTW, tomorrrow is the 38th anniversary of the Apollo 11 moon landing. Check out the on-board computers that got 'em there and back - with 72KB (yup, KILObytes!) of memory:
http://en.wikipedia.org/wiki/Apollo_Guidance_Computer 
