I think lasers are pretty wack when you think about them through this lens. A small, wand-like object in your hand can make light appear from seemingly nowhere. If it’s powerful enough it can set things on fire or blind people. Not to mention larger ones like laser cutters or the LLD, used to destroy missiles midflight. Thats sure to blow some feudal peasant minds
Smart phones. Not even Star Trek could predict we would all be walking around with a slab of glass that is exponentially more powerful than computers that took up entire rooms, can communicate with others sub-second via voice, images, video, or text, can access the sum total of public human knowledge at the blink of an eye, and can guide you to any location with a map for everywhere you want to go. It’s really powerful stuff and it’s in everyone’s hands.
Dick Tracy predicted two-way wrist radios decades ago. My Apple Watch does that plus more.
We’re getting close to 100 years on Dick Tracy, the comics started in 1931. Not even sure that was the first wrist communicator in fiction TBH.