Potable water.
Very good.
The fact that we take it for granted would be astounding in some parts of the world.
Roads. The sheer magnitude of paved roads is amazing.
Picking a doper at random… Yllaria*. My car is sitting on my driveway, and I can almost certainly travel an unbroken paved path to YL’s door, assuming I made the proper turns along the way. This holds true for the majority of US dopers, excepting those on dirt roads, etc. Thinking about this always boggles my mind.
*Random search upthread for faraway locations. Stockton’s a long ways.
Our hands and our ability to use them. For instance, the other day I was eating some chips. As I was trying to shovel these things down my gullet, some “chip debris” feel out of my mouth and was well on its way to the floor.
Except, with out even thinking about it, I was able to catch the wayward chip as it fell from my mouth, bounced of my belly and straight into my waiting hand.
Seriously, if you were to program a robot arm (or whatever) to do that exact same thing, it would take an ass-load of computing power just to pull it off. The fact that we can do this with out even thinking about it, amazes me. Even more so when you know that all the power in your brain could only light a 40 watt lightbulb.
If you’re ever really bored, try using Google maps to see the farthest you can obtain driving directions for (without having to include ferries etc).
Lisbon - Ho Chi Minh City for example.
Car and truck tires. When you consider the stress and temperature extremes they are subjected to and the amount of miles they can last now vs. the cost…they are downright miraculous.
Oil. Specifically petroleum.
It’s organic waste material that we suck from the ground and it powers civilization, and gives us plastic. How neat is that?
Suntan lotion. Amazing!
The rays of the sun are bad, but just rub on some cream: not bad anymore! IT’S A CREAM THAT STOPS THE SUN!! :eek: Blows my mind!
Oil, gas, fossil fuels. Every time I turn on the heating in my flat I think to myself “This is being heated by time-shifted energy from the sun, captured by plants millions of years ago and yanked out of the ground and pumped to this boiler so I can be comfortable.” It’s mind-boggling!
Then I think of the environmental consequences and get all depressed.
So many amazing things. And many good ideas here.
I remember at about 10 years of age in 1970 thinking how cool it would be if I could mount a camera on a small remote controlled plane and dog fight with it.
Now a computer can do it for me. Any plane, anywhere, any time.
Having seen in Hawaii what goes into growing pineapples - it’s all hand labor, one plant takes more than a year to make ONE PINEAPPLE, etc - I am constantly amazed at how cheap pineapple is, and know somebody is clearly getting exploited for it.
Not just those on the 48+Alaska, but also Canada and many all over the continent. When we were in Costa Rica, one of my coworkers would sometimes look at the Panamericana and exclaim “do you guys realize how fucking LONG that road is?”
Consumer goods in general amaze me. $4 t-shirts?! Cotton grown in one place, shipped somewhere, refined into thread, woven into cloth, shipped somewhere else, cut and sewn into shirts, shipped across an ocean, trucked across country, and put out for sale for a price that’s less than the value of an hour of cheapest possible labor? Mind boggling.
I have always been impressed with the engineering on a car or truck differential. Ingenius invention.
Washers and dryers! If you’ve ever lived without one, you know what I’m talking about! I can only imagine the difference their development made to the lives of millions. Especially women. Consider just diapers alone! Mind boggling!
Hi-fidelity phonograph records (though they probably don’t count as every day any more). I’m amazed that all those variety of sounds can be recorded mechanically and reproduced by a little needle being pushed around. That to me is much more amazing than digital recording.
A lot of mundane things are like that. Iron was created in the core of a dying star and trapped inside rock for billions of years before someone dug it out, melted it down and made the raw materials for my kitchen knife.
Someone isn’t getting paid. – When something is too cheap, someone isn’t getting paid.
Books are pretty damn awesome. A way to transmit ideas to other people, people you probably won’t ever meet, possibly even across centuries or longer? Whoa…
Once while living in Seattle (as frequently lost newbies – in those dark times before the internet and GPS), we couldn’t find Aurora*. One of the locals said: “It runs from Vancouver to Tierra del Fuego… surely you’ve seen it?”. 
*hoping my memory is correct; PNW dopers help me out here. Isn’t Aurora Hwy 99? It actually does seem to run all the way thru Mexico. Apologies if I’ve misremembered this.