The Scanimate was a predecessor to today's ever-more-complex visual animation systems, such as those used to produce films such as
Shrek and
Toy Story. It, however, was not digital; nor was it a batch-render system! The Scanimate was a completely analog 'computer' which was used to produce animation effects on video in real-time.
Perhaps the most well-known sequence produced by Scanimate was the 'targeting display' shown inside the first Death Star during Star Wars Ep. IV. As the Death Star orbits Yavin's parent gas giant, a display shows the moon moving out of the planet's penumbra, with a scrolling clock which somehow never matched the numbers we hear from the Imperial Announcer: "The Rebel Base will be in firing range in five minutes." In any case, that whole sequence of the moving moon target was produced on Scanimate, which means that it was being shown real-time for filming.
Some other sequences of this Goldbergian box showing off its chops include the opening sequence to Logan's Run (the series) as well as various bits of animation from The Beatles' Sergeant Pepper.
According to the Internet's Scanimate Shrine (at http://scanimate.zfx.com):
"The Scanimate is an analog computer system that was built by the Computer Image Corporation of Denver, Colorado in the late sixties and early seventies. In all only eight machines were ever produced. It was used on many famous jobs over the years, and many of the people that were involved with its development, operation, and care and feeding have gone on to do significant things in a variety of places all over the world."
According to this site, there is only one remaining functional Scanimate in the world as of 2002, and the author of the Shrine above has it in his basement, the lucky dog. The site above has mpeg clips of Scanimate sequences, including the Death Star sequence.
Information for this writeup came from the above-listed website, as well as from several sites referenced from there. For more information on video synthesizers in general, see: http://www.audiovisualizers.com/toolshak/vsynths.htm