Some things i learned about gis

Relatively straightforward way to cluster spatial data

http://en.wikipedia.org/wiki/K-means_clustering

data vis

http://processing.org/learning/topics/collision.html

Polymaps

http://polymaps.org/

Raphael

http://raphaeljs.com/

sweet map styles

http://cloudmade.com/

indexing of all things spatial

https://simplegeo.com/

nice looking raster and loads of data

http://www.naturalearthdata.com/downloads/50m-cultural-vectors/50m-populated-places/