1. What pattern do Sunflowers, Pineapples demonstrate?
http://www.iit.edu/~krawczyk/rjkbrdg05.pdf

2. Lissajous Figures
http://www.ngsir.netfirms.com/englishhtm/Lissajous.htm
http://perso.orange.fr/olivier.granier/meca/simul/lisajou/simul.html
http://www.math.com/students/wonders/lissajous/lissajous.html