This is a fun animation because it is quite simple and hypnotic. For each iteration hand one rotates 360 degrees once, hand two rotates twice, hand three rotates three times, and so on.
I discovered this quite a while ago when I got into Quartz Composer, and I've finally got around to recreating it using CSS transforms. I'm sure it's been done before, but I haven't found an example quite like it. There's something satisfying about this type of visual representation of numeric sequences and relationships.
I came across another interesting effect because of the way I used CSS transforms. I found that if I just gave the box an outline, instead of placing a marker at the top, it resembled a Spirograph.