This is a picture of part of the Newton fractal corresponding to the polynomial z^9+z^6+z^3+1, made using a program I wrote in Mathematica. Click for higher resolution.

Part of the Newton fractal for z^9+z^6+z^3+1.

This is an amazing picture from Mathematica's documentation on DivisorSigma, rendered in much more detail. Click for very high resolution.

Plot under 'Neat Examples' in Mathematica's documentation on DivisorSigma.