Originally Posted by Dr. Smith

Fans of '50s science fiction movies are very familiar with the Theremin (though it dates back decades earlier), whether they know it or not.

Rocketship X-M (1950)
The Thing From Another World (1951)
The Day the Earth Stood Still (1951)
It Came From Outer Space (1953)

..And later...
Ed Wood (1994)

It was one of the first electronic instruments, and inspired later inventors like Robert Moog. The Beach Boys used one in their classic hit, "Good Vibrations". Vintage models like the one in the video are highly sought/prized. We built one in my HS AP Physics class.

Here's another video of the inventor—Leon Theremin—playing one himself.
Leon Theremin playing his own instrument

Theremin

Theremin World

Another early electronic instrument—designed to be played over the telephone—the Telharmonium.
Magic Music From The Telharmonium Documentary

Doc