Are you just starting out?
There are several options. Fractal Noise scaled a bunch in Y and not so much in x plus Colorama.
Shape layers with repeaters.
There's no single plug-in that will do this with one click. Tell us a little about your experience and maybe we can point you to the right tutorial.
I'm not starting out, I just was curious if there's some good method for this. And that fractal noise + colorama is exatcly what I was looking for, thank you.
Glad I could help...