No, it will be in the top 5 tho, but Bitcoin is decentralised just like the 3d printer. Yes the 3d printer, i believe that machine will be in oure homes within 10 years. Think about it; you are able to download just almost everything and print it, even food and organs, printing entire homes is in testing stage, it will all be possible.( good for long space flights to settle on Mars) A high quality 3-d printer will change the world big time.
Bitcoin,robots, 3-d printers will all be part of the next industrial revolution; enjoy the ride!
but you will need materials right? what kind of materials would you need for, lets say a potato?
I think 3D printing for the end user is being hyped too much.
It is MUCH more feasible that you'll have custom printing and front-porch delivery of items than everyone having a 3D printer that can sinter metals or create complex structures out of multiple materials.
Unless of course we have a major break through in nano assemblers.
As to the actual question of what would be the most important technological achievement:
It is hard to tell because historically people have been incredibly bad at predicting new technological advances accurately.
I love old documentaries about how the future could look like.
In my eyes global interconnection and information exchange, cyberspace if you will, is the most significant achievement.
We tend to underestimate technologies that have a profound sociological impact.