I've been playing around with my own version of the cellular noise node and have decided to release it for free on gumroad for anyone who's interested. It's a pretty versatile fractal pattern that can generate a lot of random looks, from fire and water to mountains and lichen.
Update 9/7/19: New improved version of the node includes more noise types and refined controls!
Update 1/8/20: Fixed some issues and added 3D Noise support
Update 5/2/20: Added controls for a seed