I gave a colloquium talk in the math department of Sungkyunkwan University on 9 April 2009. Here are the slides and worksheets I used in the talk:

slides pdf: skku-sage.pdf

slides source: skku-sage.tex

the Cython worksheet: Cython.sws

the ginkgo leaves @interact demo: leaves.sws

the public worksheet I showed is at https://sagenb.kaist.ac.kr:8066/home/pub/5/