I am a sucker for data visualization. I am less enamored with infographics these days as I have noticed some hijacking of the medium for public relations stunts. Taking a few anecdotes and drawing some arrows does not cut it in my book.
Here are five libraries that I picked out from Gube's post:
Highcharts offers seven charting types such as line, pie, and bar. You can zoom in and out of charts. It offers tips with more information about data points. Documentation is excellent.
StyleChart is an API for creating charts. According to Gube, it includes tooltips, legends, and 19 types of charts including 3D pie, 3D bar graphs and Pareto charts.