Silverlight & WPF Chart - http://visifire.com/
"Visifire is a set of open source data visualization components - powered by Microsoft Silverlight & WPF. Visifire is a multi-targeting control which can be used in both WPF & Silverlight applications. Using the same API, charts in both Silverlight & WPF environments can be created within minutes. Visifire can also be embedded in any webpage as a standalone Silverlight App. Visifire is independent of server side technology. It can be used with ASP, ASP.Net, PHP, JSP, ColdFusion, Ruby on Rails or just simple HTML." - Edmund Tay