It's amazing how many sci-fi concepts later become real science. Some science fiction writer dreams up an idea (such as Arthur C. Clarke writing about orbital satellites) and someone comes along later and says, "Hey! Let's see if we can do that!"
How about the "death rays" of '30s/'40s pulp novels? Now we have lasers. Okay, not in handgun form, but the technology exists and the military is looking for ways to weaponize it (shooting down missiles, jets, and satellites, for example).
Those pulps also brought us spaceships rocketing across the galaxy. We aren't quite there yet, but only a few decades later, we did manage to land on the moon.
Star Trek communicators inspired engineers to develop cellphones (which, ironically, are smaller and more futuristic than those dreamed up for the 22nd-century TV series).
Sci-fi also brought us lifelike holographic images. Although we do have primitive video holograms today, we're not quite there yet. On the other hand, another promising offshoot from the concept is holographic storage. Companies are already coming out with storage devices that use holograms to store data in three dimensions, offering the potential for quantum leaps in storage capacity and speed. Rumor has it that the next generation Nintendo gaming console will use holographic storage. (Here's a video that explains the concept in layman's terms.)
And now a scientist has developed something much like a Star Trek "dermal regenerator." It's a handheld laser device that promises to seal up skin with less leakage than with sutures, and less scarring to boot!
As far back as as 1895, authors have been writing about "beanstalks," "skyhooks," and "space elevators" as means of getting from the Earth into space without needing a spaceship. The latest thinking in space elevator technology involves high-tech materials like carbon nanotubes and boron nanotubes, which didn't even exist two decades ago. Now scientists are trying to drum up backing for projects to build these elevators within the next 30-50 years. Theoretically, this technology could lower the cost of getting cargo into orbit from millions of dollars per pound to tens of dollars.
But that's not all. Because spaceships won't need to take off and land on Earth's surface (which requires enormous expenditures of fuel), ships can be made smaller (or have more cargo capacity in the same volume). Even better, because the space elevators are in geosynchronous orbit, they offer the ability to serve as rocket boosters, using the Earth's centrifugal force to sling ships and unmanned cargo at great velocity. This promises to shorten travel times to other planets (and back, if we build space elevators on the Moon, Mars, and elsewhere).
Worried about this huge elevator falling to earth and killing millions? Don't be. If the cable(s) break, the centrifugal force on the counterweight out in space will cause everything above the break to be hurled upward and outward. The part of the cable below the break will fall to earth. But because the paper-thin ribbon cable is made of carbon nanotubes (i.e., flammable), much of it will burn up on reentry. The lower part will indeed reach the ground, but with the impact of dozens of miles of fluttering, unrolled toilet paper, not steel girders.
Cool stuff! And all brought to you from the minds of science fiction writers.
P.S. For novels involving space elevators, written in different decades, see Arthur C. Clarke's The Fountains of Paradise and Charles Sheffields' The Web Between the Worlds (both published in 1979), Kim Stanley Robinson's Red Mars/Green Mars/Blue Mars trilogy (1990s), and my own The Mars Imperative (2007).