In 1961, Robert Heinlein envisioned the concept of screensavers before they existed. In his book 'Stranger in a Strange Land', he wrote: 'They went to the living room; Jill sat at his feet and they applied themselves to martinis. Opposite his chair was a stereovision tank disguised as an aquarium; he switched it on, guppies and tetras gave way to the face of the well-known winchell Augustus Greaves.' The typical aquarium-style screensaver has become classic since the 90s.
Stranger in a Strange Land [book] Putnam, 1961