Is it the moon landing, voyager, finding the higg's boson, decoding the genome, or have they been surpassed this week by the regeneration of spinal cord and partially reversing paralysis?
Wonderful story, but not as much fanfare as I'd have like to have seen. http://www.bbc.co.uk/news/health-29645760
Disc brakes FTW
There is no greatest..they're just steps along the way.
A friends then girlfriend, now wife,after much deliberation decided it was probably the teasmaid!
"Well it wakes you up with a fresh cup of tea!"
Gobs well and truly smacked over that one.
the Cavity magnetron (cos it has a cool name too) 😉
3d porn
The Haber–Bosch process
or possible directional hifi cables
Chicken McNuggets 😉
Rockshox pikes.
Edit. Naw, reverb. Definitely the reverb.
The printing press.
650b or Blu-tac.
Its a matter of how you measure 'great'. There are technological pinnacles that benefit very few (globally) and are of interest to only a few more. An achievement like regeneration spinal tissue - magnificent for the very few who have access to health care. Eliminating common illnesses like polio are of far greater significance to mankind broadly though.
Organ Transplants.
..until they can grow new organs.
In no order.
Wheel
velcro
zip tie
internet
Brewing.
There is no greatest..they're just steps along the way.
I agree, there are a lot of "giant's shoulders" being stood on in that operation.
Can we have the written word, without it the steps would be forgotten?
Fire
Cake
Contraceptives
I'd hazard a guess at Antibiotics but whether that would come under the term of modern early 20th century medical advances could be argued till we die of old age.
or have they been surpassed this week by the regeneration of spinal cord and partially reversing paralysis?
Lots of experts urging caution in assessing this advance owing to the relatively straightforward nature of the patients injury. Important yes but only the first step. Pun intended.
Quantum electro dynamics.
Boeing 747
Sanitation and fresh drinking water on tap. Maybe elastictrickery too
Something agricultural related (irrigation or the plow or even just agriculture itself) as it allowed humans to move past the hunter gatherer stage of development
Convincing women to sleep with them.
The atomic bomb
If they manage to actually land the Rosetta lander on the comet next month, that is going to be pretty impressive.
http://en.wikipedia.org/wiki/Philae_%28spacecraft%29
Internet porn
Scientific or engineering.
Engineering - probably the steam engine.
Scientific, understanding the principles of evolution.
I'm gonna go with electricity.....
Crumpets
Something agricultural related (irrigation or the plow or even just agriculture itself) as it allowed humans to move past the hunter gatherer stage of development
On the other hand that has led directly to over-population.
Tweed.
Looking at earlier suggestions I reckon the printing press and sanitation probably just have the edge over brewing. But not by much.
Glass.
I could stand on a sandy beach all day and it wouldn't occur to me to turn it into windows.
Red IPA
Beer's a good one, it enabled most people to drink water free from contamination 'cos the alchohol killed the bugs. Everybody drank 'small beer', even children.
Of course scientific discoveries are important, but things that help keep people alive day-to-day are too.
The Transistor
Contraception
Another contraception vote here, giving women control over their bodies
Electric generator
Clearly it's 650B.
I think we're confusing 'greatest achievement' with 'most beneficial to mankind.'
Our greatest achievement, unequivocally, is putting a man on the moon and bringing him back safely.
Whilst this had far-reaching benefits, many of which aren't immediately obvious, I wouldn't like to stand it up against things like antibiotics or vaccination in terms of how much better off we are as a result.

