[math-fun] Holy cow, I found the equation for melanoma.

gosper.org/melanoma.png Plot3D[-Log[Abs[-((I EllipticTheta[2, 0, I E^(I t) r])/Sqrt[2]) + EllipticTheta[2, 0, E^(I t) r]]], {r, .99, .9999}, {t, .78, .79}, PlotRange -> {0, 239}, PlotPoints -> 69] --rwg