The Atomic bomb: Following its infamous use in the 2nd World War 1950's engineers came up with a bizarre set of uses including setting off a series of bombs to build giant canals (from Bill Bryson's wonderful autobiography) and even a plan to use atomic explosions as rocket fuel.
Following this period of mad ideas we now have a well developed sense of the limitations of nuclear fision.
The second example is illustrated by a quote from Douglas Adams:
"[of humans] ...a race so backward they still thought digital watches were cool"
My dad used to have an analogue watch which I was allowed to wind up every evening. My interest didn't last, I clearly remember hounding the first kid at school who got a digital watch, I wanted to keep pressing the buttons to see those magic red figures light up. Unsurprisingly he wanted me to buzz off and stop wasting his watch battery. The infatuation with digital watches we all had didn't last of course, if you're wearing a watch as you read this its probably an analogue watch run by a quartz battery watch. Again, following a fascination with one technology (quartz digital watches) we quietly learned how to use the technology properly - the hype didn't last.
Neither of these examples are perfect, you could argue that the public have an overly developed fear of nuclear radiation which affects our present use of nuclear technologies. You could also argue that the popularity of analogue watches is linked to aesthetics as much as practicality. However, the analogies are there to illustrate the idea rather than be completely water tight and I think they work rather well.
So are we in the 'cool digital watches' period with the virtual globe technology? I would say we are, you don't have to look far to find Google Earth projects with badly thought out icons, overly bright lines and a bafflingly complex structure in the places column. The faster we get over our infatuation the better.
Which isn't to say Google Earth isn't a great tool, I wouldn't be blogging about it if I thought it was rubbishj, it's just we're not using it correctly yet.