What's a good f/oss GDI+ (System.Drawing) based graphing and charting component for .NET?

Question

I want to create basic line, bar, pie and area charts for .NET 3.5 WinForms and I'm interested in finding a free, mature, open-source .NET (preferably C# based) project to help me accomplish that. I would consider a WPF based project, however I'm more comfortable in GDI+ so I'd rather it used System.Drawing and/or GDI interop as its base technology.

Thanks!

Answer 1

Take a look at ZedGraph: http://zedgraph.org/wiki/index.php?title=Main_Page

Answer 2

This one's quite nice: zed graph

Answer 3

ZedGraph. 'Nuff said.