ZedGraph is a class library, Windows Forms UserControl, and ASP web-accessible control for creating 2D line, bar, and pie graphs of arbitrary datasets. The classes provide a high degree of flexibility - almost every aspect of the graph can be user-modified. At the same time, usage of the classes is kept simple by providing default values for all of the graph attributes. The classes include code for choosing appropriate scale ranges and step sizes based on the range of data values being plotted.


http://www.codeproject.com/csharp/zedgraph.asp?df=100&forumid=26087&exp=0&select=1605903#xx1605903xx
http://zedgraph.org