Many of the comments on that one were negative too. What is interesting for one person is dumb for another anyway. For me, both the css-logos, and this QR code

Many of the comments on that one were negative too. What is interesting for one person is dumb for another anyway. For me, both the css-logos, and this QR code on a cylinder were nice to see from a theoretical point of view, but I don't see any practical use.