sunpath information

Does anyone have any experience using sunpath data in grasshopper? Ideally, I'm looking at stuff like this:

http://www.livearchitecture.net/archives/741

but also create my own sun path diagrams (on polar grids) based on latitude: (so that way I can make my own pretty graphics instead of relying on someone else's)
http://luxal.eu/resources/daylighting/sunpath.shtml

any thoughts, references, or experiences?
thanks