@Thesonofhendrix
Fractals can be done with volumetrics: https://youtube.com/watch?v=WSQFt1Nruns
If you are determined you can implement more formulas like Mandelbox, Julia and Sierpiński sets.
Just beware, that render times for volumes can be long - depending on your shader setup.
I followed the tutorial, made some tweaks along the way and rendered with Cycles:
In last two I used selective emission on both surface and volume.
