The best thing since... oh, that's not on the list
The Atlantic magazine published one of those articles based on the latest that I really should ignore and not take too seriously but can't help reading -- Fallows, J., "The 50 Greatest Breakthroughs Since The Wheel" in "The Atlantic" p.56(9) (Nov. 2013). This time it was the 50 greatest breakthroughs since the wheel. They asked various scientists, historians and technologists to rank a list of innovations for the article, and then put them together into a nice feature.
I'll spoil the ending for you by telling you that number one on this list was the printing press! I was surprised that the telegraph only made it as far as position 26 because as an acolyte of the Economist writer Tom Standage ("The Victorian Internet"), I do think that the step change between being unable to communicate faster than physical matter could be propelled and being able to communicate at the speed of light represented some fundamental cusp in human history rather than any kind of marginal improvement, so think I would have pushed it further up the list. Damn. There I am getting caught up in thinking about the list again.
Oh and one more thing. The most amazing fact that I think I saw in the article concerns the sequencing of human DNA. The article notes that in the past 12 years the cost of sequencing human DNA has fallen to a millionth of its previous level. That's an astonishing six orders of magnitude cost reduction in a decade. Now I can't decide whether DNA sequencing or 3-D printing will feature in some future list as the most important technological breakthrough of our current era.
In the future, everyone will be famous for fifteen megabytes