Free Interactive Graphs With Open Flash Chart
Open Flash Chart is a free project that allows you to integrate flash graphs in you website. There is support for all of the commonly used graphs like bar charts, line charts, area charts, and scatter plots. The flash component allows the user to hover over points of the graph and view labels explaining the point (see screenshot above). This feature is what sets Open Flash Chart apart from other chart/graph apps. Check out the website for tutorials and examples. There are other static graphing libraries like Google Charts that are clean and useful but static.