Lightweight javascript graphics using SVN Vectors
Over at my favourite design website, they are discussing how to make a table of data gracefully upgrade itself from a table to a graph.. but to still be available as a table to non-supported browsers and spider-bots.
http://www.alistapart.com/articles/svg-with-a-little-help-from-raphael/
NOTE: Be aware, that at the time of writing, there is a bug that orders pie chart items by the highest to lowest value. You can track the bug (and the fix) at the repository at GitHub.
NOTE: Be also aware that if you have values with a large difference (one is 1,000,000 and the other is 10), that it currently has a rendering issue that prevent the whole graph from loading. You can track the bug (and the fix) at the repository at GitHub.