Sort have been doing some research on Doyle spirals which lead to the concept of Circle Packing. Looked all over the place for programs (free of course) that does these but to no avail. Sort of faked it using a seamless texture that I created and then running Mathmap Droste and also Sculpture Generator (program created by Carlo Séquin) with that texture. As a side note, I did enter a wish list for such a feature with G'MIC, but don't know how hard it would be to implement.