As it says on the tin, what are some ordinary items that we use in our daily lives that fascinate you?
The thermos: How do it know?
I’m fascinated that I can walk through a nuclear research reactor pretty much any day I want, and also the facility that fabricates the nuclear fuel for the facility. Way cool stuff.
I’m also fascinated by SpaceX, but have no connection to them at all. Elon Musk is a hero of mine.
Fucking magnets. How do THEY work?
Gloves. When you take them off, they still look like a hand.
Glass.
It’s made of sand, people… SAND
Oh…and my Swiss Army Knife. I like opening all of the little bits out (including removing the pin, toothpick and pen that slot into the side, and the teeny screwdriver that twists into the corkscrew), then putting it all back together.
Yeah. I know. :o
Plastic boots, and plastic tents.
You can rain all you want… F*** you Nature 
Watches. This is now ancient tech in comparison to the new gizmos, but they’re still beyond superior. Winding while you just moves your arms? Doesn’t crash? USB, my ass. These things tell you the elevation without a microchip.
My ink pen. No, I’m not old enough to have used a quill 
but fountain pens were really messy though often expensive, I think. Banks gave them out and it was a big deal. You know the old cartoon of an ink splotch on a guy’s white shirt pocket? That probably doesn’t happen now but used to clothes were regularly ruined by ink. Few of us could get the hang of refilling a pen so when the disposables came out it was heaven. I can write as much as I want then throw them away. Just, wow.
The potato peeler.
Simple as hell. It’s the definition of purely functional design perfection.
It’s just a stupid piece of stamped and formed metal with a sharpened edge, and yet it’s so fucking good at what it does it’s ridiculous.
Also a corkscrew wine bottle opener. I don’t drink wine often, but I did wait tables. When someone ordered a bottle, I got to take it out (the kind with the arms you keep in your apron), pop it on top, aim it (which is foolproof), screw it down and make the arms go up, push down on the arms and serve.
Not one of my best skills though. So my second favorite invention was the wine strainer-- a simple little sieve to catch all the broken cork I just carved from the cork into the bottle…
Pinwheels. So simple and yet they radiate a sense of joy, of hope, of optimism.
Knives and pocketknives. One of the oldest, simplest tools known to mankind, yet still one of the most beautiful, elegant and downright essential
Refrigerators or air conditioners or anything else relying on phase change.
AMAZING!
Staplers.
I especially like the old, old ones that are made of cast metal and weigh about 20 pounds.
Books, newspapers and magazines. There is just something facinating about words printed on paper. I know I can get the same information from an LED screen but, dangit, it’s just not the same!
There is an awesome feeling of invulnerability when you are outside in shitty weather and have your waterproof gear on. Same when it’s cold outside but you’re warm and snuggly in your clothes.
Rema bicycle tube patch kits. It’s like a little time capsule, I’ve never seen a product with so little design change.
Cotton candy and bubble wands have fascinated me since childhood. 