Birth-control pills would outshine all the rest, including the silicon chip. 
Not so anymore (sort of): Tricorder
There’s always Dolly the sheep. I’d bet that a lot of folks back in 1950 would be amazed that it took over 50 years for there to be cloning.
If I look back to my childhood (1950s and 60s) cellular technology is the one thing we have today that most closely resemble something we were told back then that we’d have “by the year 2000”. The instant, pocket-portable communication devices we have today sort of combine Dick Tracy’s 2-way wrist video with Star Trek’s communicators. Desktop PCs (never mind notebooks!) and the internet are beyond anything imagined when I was a kid.
But I’m still waiting for my personal jet-pack.
I came here to mention GPS, but somebody beat me to it. Worth mentioning again.
I’m fairly techno-savvy, but I recently upgraded my phone and got one that’s GPS-enabled. I’m just stunned & amazed…this is the coolest thing EVER. It knows where I am! And the location of the nearest Mexican restaurant!! And can give me turn-by-turn directions!!! :eek: :eek: :eek: *That * is just astounding.
It was well after 1957, but I remember in a James Bond movie (which one?) that when Q was taking Bond into his secret laboratory, he didn’t open the door with a key, but rather inserted a plastic card into a slot next to the door to unlock it. That was way cool gee whiz stuff.
Now, I have card sitting in my wallet that when waved in the general vicinity of a reader in an elevator in my office building (or when I waggle my ass near the reader) will select and unlock the proper floor. A similar thing would be electronic toll transponders–you can drive your car through an arch over the road and it will automatically zap a box on your windshield and bill you for the proper toll, sometimes travelling at 60 mph.
Travelling through my wallet, I think my Automatic Teller Machine/Debit card would be a big shock for a time traveller from the '50s. It is a pretty far out idea that you can walk into any bank (or most delis, supermarkets and McDonalds), 24 hours a day, stick your card into a slot, push some buttons (or touch a screen) and have the machine spit cash into your hand. Plenty of early science fiction had the protaganist handing over a gizmo to transfer credits from his account to buy something. My debit card is just about the same thing.
Also in my wallet is a thin plastic card which pays my subway fare. If I didn’t have a monthly card, I could put $2 into a machine to get a slip of paper with an metalic strip on it to use and throw away, rather than using a token that would be collected and reused. Even more frivously, I have a gift card from Dunkin Donuts that I charge with money to get my morning coffee.
Anything environmental. The whole green movement started in the 1960’s with the hippies. And wouldn’t a 1950’s person be shocked to see newsreels from that time?
Talking of the internet, one of the shticks in Blake’s Seven was the ability of Orac to access any computer that had a “Tarriel Cell”. And now we have wireless internet, and Orac (bar “his” obnoxious personality) seems much less impressive. Even by the standards of a few years ago, it astonishes me that I can have a cheap wireless device that can transmit data fast enough and accurately enough through a freakin’ wall to maintain a broadband internet connection for up to eight computers at once - and my father-in-law can drop by with his laptop and hook up just like that!
Completely automated warehouses. I worked for Heinz last summer in a warehouse next to an automated one (Europe’s biggest warehouse, in fact). When we finished packing a crate, we slapped a barcode onto it, a forklift came and picked it up and put it on the conveyor belt, which took it into the other warehouse. Robots in the warehouse picked it up on the other side and placed it in the correct place on the shelving (which was ridiculously tall, if I remember) and then removed crates from the warehouse when they were needed.
The statistics for the number of crates processed in a week by the warehouse were ridiculous - you’d have needed masses of workers to match the work performed by a few robots.
Eh, there was yogur in Spain in 1957. And before. Yogur is an exotic food? cleans up the last of her glass-pot Danone
My grandmother’s vote is for sex reassignment surgery. This internet thing is interesting sort of but she just can’t sit still long enough to give a damn.
Scars not healed yet? 
How cheap modern electronics have become, so that they’re essentially disposable. Back in the 50s there used to be this guy called a TV repairman, see …
Howzabout computer aided graphics in motion film?
Watching a newer movie, like Pirates II, the other day got me thinking how awestruck someone from the early film years would be watching this right now.
I think the visual stuff is more impressive than the behind the scenes thingies mentioned in this thread. How do you get more visual than a hi-tech sci-fi movie shown on a big screen with digital surround sound?
What got me thinking about this was going from watching “Blue Skies” with Astaire’s famous “Puttin’ on the Ritz” dance routine and wondering how they did that sort of effect back in the day and then watching “Pirates II” and thinking, “man, the guys that did the video effects for “Blue Skies” would be incredibly impressed with the average stuff we see on film today.”
Nava, of course yogurt is an ancient food that people have eaten for thousands of years. It’s just that an American in 1957 never would have heard of it, of if they had it would be some bizarre foodstuff that crazy foreigners ate, not real people.
Long distance phone calls were pretty common before 1957. A bit expensive to most people, but still not uncommon. And documents and photos could be sent over phone lines too, though not as fast, and with rather poorer quality (and I don’t think they could be done in color). Granted, those technologies have improved, but they did exist in '57.
As others have mentioned, TV dinners were certainly “heard of” by 1957, and were not uncommon in American households. They weren’t very good, but again, the advance has been in quality, not a “gee-whiz!” introduction of something unfathomable.
Not so. Not for 1980, anyway. By the late 1970s, amniocentesis was commonly used to determine the sex of an unborn baby. We had a child born in 1979, and were offered the opportunity to know its sex in advance. We chose not to, not because we were Luddites, but because we preferred to find out at the moment of birth. Ultrasound was becoming common around that time as well, though it wasn’t nearly as reliable a method of distinguishing sex.
I think a lot of younger people have a rather exaggerated idea of how “primitive” things were just a few decades back. Which is not meant to insult anybody; it’s difficult to have perspective on things you didn’t experience. And I also don’t mean to suggest that a lot of what is common today wouldn’t be startling to the average man-on-the-street from 1957. Most of the real whiz-bangs, though, are entirely due to the microchip processor, and the “digital revolution” it made possible. And I don’t think many people in 1957 saw that coming. Certainly not so fast, getting smaller, faster and better in such leaps and bounds, and with such enormous ramifications to everyday life.
Damn—that was going to be my dark horse entry. To think of how many people would be dead, gibbering and restrained, or subjected to desperate “shock” treatment who now could just be leading normal lives with a couple of pills a day…yow.
Hell, the women who are taking places in war would probably be bewildering.
This has been mentioned before, generally, as ‘non-invasive surgery’, but what still impresses me a lot is the laser eye surgery I had done five years ago. For someone from the 50s, I think it would count towards a lot of giving-sight-to-the-blind points.
Well this is only 22 years ago, but the Asimov novel Robots and Empire predicted at least some of the social aspects of the Internet. One of the human colony worlds had a culture where people only ever interacted outside of their immediate family via video conference calls for most of their lives. Everyone was extremely awkward when dealing with people in the flesh; courtships were highly structured and ritualized affairs. Things aren’t nearly that extreme today, of course, but I have heard reports about the odd sense of isolation that can happen to people who socialize more online than off.
I was just going to ask…did any SF author ever predict MySpace?
Computerized animation I think would have come as a surprise to people from the 50’s – not so much that it exists, but that it’s virtually replaced traditional ink & paint animation, relegating the old Walt Disney style to independent short films and Saturday morning cartoons.