Not a new conceptI read about this back in 2003. https://www.wired.com/2003/08/random/
I also remember reading, at the time, that the lamps were pretty much irrelevant. The noise in the camera's CCD element itself (easily sampled by simply leaving the lens cap on) had just as much entropy as the pictures of the lava lamps.
Pick a number!I saw headlines about these lamps but didn't have a chance to read more until now. It's an interesting approach for sure. I wonder if they regularly reorder the location of the lamps or swap them out for newer versions to keep the action fresh (or even if any of that might matter).
I also remember reading, at the time, that the lamps were pretty much irrelevant. The noise in the camera's CCD element itself (easily sampled by simply leaving the lens cap on) had just as much entropy as the pictures of the lava lamps.