Hehehe.... I might have typed some of the same code into a Commodore 64. I do know that was the first place I ever made a mandelbrot. Since it was interpreted basic it definitely was slow. You could watch each pixel slowly appear.

I love this stuff and haven't had the time to full dive into it for awhile. I will admit on this subject these days I kind of live in a bubble. I do my own experiments without seeing if someone has already done them. About the only fractal like things I've used from outside of mandelbrot and myself for awhile are perlin and simplex noise functions.