A little over 14 months ago I blogged about how Microsoft was making available a free download of charting controls for both ASP.NET 3.5
and Windows Forms 3.5.
You can download and use these runtime controls for free within
your web and client applications today. You can also download VS 2008 tooling support for them. They
provide a rich set of charting capabilities that is easy to use. To get a
sense of what all you can do with them, I recommend downloading the ASP.NET and Windows Forms sample projects
which provide more than 200 samples within them. Below is a screen-shot
of some pie and doughnut chart samples from the ASP.NET sample application: