I am ancient enough not only to remember it, but to have watched it as nature intended at primary school every week before a programme. I was always mesmerised by it, but my unimpressed teachers used to complain that it wasn't as easy to understand as ITV's schools clock.
The diamond mechanism itself is fascinating and it was very satisfying to work out how it worked.
The diamond animation as outlines in Flash
The four striped version of the diamond was originally only a static caption card, intended for use in place of the mechanical model in intervals less than two minutes in length.
I always wanted to see it being animated. Hence another lame mock that I produced, as always, in Macromedia Flash 8.
As I'm exclusively using GNU/Linux these days I exported the diamond from Macromedia Flash 8 as a PNG sequence. I imported that into the free software video tool Avidemux, added the music and exported the resulting sequence into an MP4 container with MPEG4-AVC video encoded using the x264 video codec and MP3 audio encoded using the LAME MP3 audio codec.
I find the overall effect is rather akin to seeing one of those 4x4 or 5x5 Rubik's cubes for the first time.