Silverlight is the new graphics and animation engine from Microsoft with a lightweight programming model for developing cross-platform rich internet applications with real languages. The runtime is .NET based and is only 4 MB to download (and download is only required the first time it needs to be consumed on the PC). Speed and performance is incredible with speeds as much as 300 to1000 times that of Flash. More Silverlight resources are listed below. 

• Getting started with silverlight - Scott Guthrie (who needs no introduction) demos how to build an app from scratch
• "How Do I?" with Silverlight 1.0
• "How Do I?" with Silverlight 1.1
• Using Blend with Silverlight 1.0
• Community gallery
• Top 3 samples in community gallery
• Silverlight Pad
• Page Turn
• Video Library
• Beijing Olympics Use Silverlight
• Channel 9 screencasts
• Watch movie trailers & videos via Silverlight

  is Silverlight is cool or what!!!:)