This image consists of 24 individual fields, which started out black when I uploaded the initial files. At the top of each hour, the field corresponding with the current hour (in UTC, of course) will change color. The colors are chosen by other computers at random.
There are two bash scripts. One is generating a random color, called hourly on each tilde server I have a shell account on (currently ctrl-c.club, tilde.town, tilde.team and tilde.club). The second one runs right on this server and will, also hourly, download the color value from a randomly chosen server and change the value in the css of the corresponding field. In case there is no valid response from the chosen server, the field will be black.
The page itself will reload once a minute to make sure the new color is displayed. (I could have used JavaScript and made sure it happens right at the top of the hour, but I'd rather not rely on JS.)
I have no more say in this. The future look of this picture will be up for a handful of computers to decide.