Free Silverlight controls are popping up a lot lately, especially WinForms-like and charting controls. Here's another chart conrol The FreeSilverlightChart by Venkata Guddanti. It uses XAML and C# to display charts on the Silverlight platform. The FreeSilverlightChart Control supports quite a lot of chart types including: Verticle Bar, Cylinder Bar, Horizontal Bar, Stacked Vertical Bar, Stacked Horizontal Bar, Pie, Area, Stacked Area, Line, Bar & Line, Area & Line, Bar/Area/Line, XY Line, Scatter Plot, Radar, Radar/Area, Funnel, Circular Gauge, Semi-Circular Gauge. 

Online Demo - Source Code