Many twisting multicolor lines.
I used my fractal program to generate this. It is used in a rather non-fractal way, so do not call this a fractal. (I will skip the tutorial on fractals, please use google if the rest does not make sense.)
The underlying formula is very simple, generally affine transformations with a light sprinkling of the sine function. The number of iterations is kept low, usually single digits or teens. The coloring is not related to Julia set membership or escape-time. The Julia set for this formula is uninteresting, and there are not enough iterations to determine Julia set membership. (Just using fancy mathematical words to say “not a fractal’.)
The low iteration count provides a nice distortion of the basic line or sine wave. Color is based on the current z-value, not the iteration count. Each iteration is colored and overlays the previous.