Lavarand

thumb|The Wall of Entropy is a wall of lava lamps at the San Francisco headquarters of Cloudflare, which was inspired by Lavarand.

Lavarand is a hardware random number generator designed and trademarked by Silicon Graphics (SGI) in 1996. The system operates by digitizing the chaotic patterns of warm wax blobs oozing inside an array of lava lamps. This data is then processed with a cryptographic hash function to produce a high-quality seed for a cryptographically-secure pseudorandom number generator (CSPRNG).