Functional Geometry
http://www.frank-buss.de/lisp/functional.html
Nice bit of drawing code.
関数プログラミングで扱う幾何学について。50 Stunning Examples of the Droste Effect | Webdesigner Depot
The Droste effect is a Dutch term for a specific type of recursive picture. An image exhibiting the Droste effect depicts a smaller version of the image