A recently dug-up Time Magazine article from 1951 applauds Zenith's "Phonevision," a way-ahead-of-its-time invention that allowed movies ordered over the phone to be watched on a set-top box, no physical media required.
Phonevision wasn't exactly a home theater PC or a Roku box, and actually had more in common with something like Pay Per View: It had three scheduled showings each evening, and you called and ordered one of the few options offered at a cost of one dollar per film. The set-top box would unscramble the picture and allow the movie to be watched on your TV. It was also limited to about 300 test subjects in the Chicago area, but they apparently loved it and Zenith was very excited about the prospects of moving "the theater into the living room." But what, you might ask, were the choices on this very early service?
The 300 Phonevision subscribers had an initial choice of April Showers, a 1948 musical starring Jack Carson; Welcome Stranger, a 1947 Bing Crosby comedy, and 1948's Homecoming, with Clark Gable and Lana Turner.
Interestingly, while the industry called Phonevision a "massive flop," Zenith president Eugene F. Macdonald loved it and considered it a rousing success, though it never penetrated very many markets and was officially cancelled in 1969. [Time, image from Early Television]