Created using Ultra Fractal.
This is a degree 4 of the White/Nylander "true 3D" Mandelbrot - for details see here:[link]
It was rendered using a wide field of view at 8000*8000 which took around 10 hours on my core2duo laptop.
Download absolutely essential !
The colouring is location based using fBm(x+flip(y))+fBm(y+flip(z))+fBm(z+flip(x)).