<a href="https://en.wikipedia.org/wiki/Lavarand" rel="nofollow">https://en.wikipedia.org/wiki/Lavarand</a><p>(CF also mentions it in their blog post: <a href="https://blog.cloudflare.com/lavarand-in-production-the-nitty-gritty-technical-details/" rel="nofollow">https://blog.cloudflare.com/lavarand-in-production-the-nitty...</a>)
What would better generate visual randomness for cryptography than lava lamps? I find this solution interesting as there are patterns to other seemingly random things in nature. For example, no ocean wave is ever going to be exactly the same, but they do follow a pattern of the tides. From a crytography perspective, how would a high resolution video of something like a beach compare as a solution?